printers display screens and speakers are __________ devices for sale

These could be standard 2D printers, reproducing text or images on a piece of paper. More recently, this category has been expanded to include 3D printers outputs - which create entire physical objects based on digital models and instructions. Of course, this latter category is a little more complicated than standard 2D printers.

Plotters are another type of output device. Unless you work in the engineering or architectural sector, it is unlikely that you"ll be regularly using these, but they are vital within these fields for converting vector images into physical diagrams. They come in the form of a large machine ‘arm’, which holds a pen (or sometimes a craft knife), which then uses specific instructions to mark a material such as paper in order to sketch out an exact diagram. This is particularly important for cases where precision and accuracy are vital, such as a blueprint.

Of course, there are too many output devices to cover in just one article. Alternatives to those listed above include haptic feedback devices, which convey information to users through motion, vibration, or force — think your phone’s vibrations, or the rumble of a gaming controller. Haptic feedback is also being trialled for use in virtual reality controllers, to pair the physical sensation of touch with the visual stimulation provided by the headset itself.

Braille readers are another example of an output device, bridging the gap between monitors and physical output devices by allowing visually-impaired users to read text by way of physical output. This is usually achieved through the use of round-tipped pins raised through holes, to simulate braille markings as the cursor is moved across text.

Virtually growing up in a computer repair shop, Naomi Bolton has held a passion for as long as she can remember. After earning a diploma through a four year course in graphic design from Cibap College, Bolton launched her own photography business. Her work has been featured on Blinklist, Gameramble and many others.

You know, none of these are really easy choices. If it"s just you working on the system, the decisions might be simple, but if you have to consider others" opinions, not so much. Let"s start with the monitor. We use this to view the work we"re doing at the time or to view a finished product. We may also use it to view videos or photos we"ve taken or found online.

Monitors come in many sizes and descriptions. To make the best decision, you should ask yourself what you"ll be doing the most with your computer. Are you just writing papers or creating presentations? Are you surfing the Internet? Are you playing games once in a while? Are they games that are not intensive in graphics? Are you making and editing videos for fun - or for a profession?

If you can keep it simple, the standard monitor is for you. If you"re playing games with intensive graphics, making videos or working with digital photographs or art, you may want a high-definition monitor. If you"re going to use a computer as your home entertainment system, you can find one that is TV-ready as well.

The size of the monitor you use truly depends on your preference. Things to consider are your eyesight, who else will be using it and the distance the monitor will be sitting away from you (assuming you go with a desktop unit, not a laptop). There are monitor sizes ranging from 7 inches as a supplementary peripheral, but normal monitors range from a 17-inch diagonal to a monster 55-inch diagonal! You could comfortably surf from the couch in the living room with a monitor this size.

Monitors are created with LCD (liquid crystal display) or LED (light-emitting diode). LCDs have layers of glass, polarized film and liquid crystals. You get electrical impulses sent through, and this causes the color to be shown and image to be displayed. LED monitors take the LCD one step further. They put a diode on the back that forces light through the layers for a sharper picture and better colors. It is said that LED monitors will last longer than LCD monitors.

Have you decided which one you want to go with? Don"t forget, you"ve also got touchscreen monitors available should you have a use for them. The most practical use of a touchscreen monitor for consumer and professional use would be to someone with a physical disability.

The next difficult decision to make will be the printer that will work best for you. Printers are used to create a tangible product to look at away from a monitor. For consumer use there are two kinds to choose from: the inkjet and the laser printer.

The inkjet printer uses a liquid ink that"s sprayed through a print head onto a piece of paper. How? Simply put, the printer interprets the signal from the computer and converts it to instructions that go through the print head. Inkjet printers are typically inexpensive to purchase, although the replacement ink can be costly and add up.

Laser printers use heat technology and specialized powder called toner or another medium (I"ve seen it with wax - it looked like crayons) that"s heat-sealed onto a piece of paper. Laser printers are somewhat expensive, though they"ve come down in cost as the technology has increased.

Both types are often available as mono-color (or black-only printer), full-color or an all-in-one printer. An all-in-one printer typically has a printer, a copier and a scanner. Some still have a fax feature as well.

You should ask yourself how much you"ll be printing and how often. If you don"t print too much, the inkjet printer may be for you. One disadvantage, though, to not printing often with an inkjet printer is that the print head can actually plug up, dry out and then not work. If you print frequently or in large quantities, you may find yourself purchasing ink quite often. Ink varies in price but ranges between $9 and $25 for about 250 sheets of text-only in black ink. The toner for laser printers seems prohibitive but usually will print up to 5000 sheets of paper per cartridge. These toners are between $80-$100 a unit.

An example of typical usage: several years ago I bought a mono-laser printer (actually, it was an all-in-one) for about $170. It was used to create syllabi for seven different classes and hand-outs for most of those classes, for my daughter to write papers for her high school classes and for my son (who discovered SpongeBob on the Internet and printed out hundreds of coloring sheets), and I prepared at least 60 tax returns in that season. The one toner cartridge lasted more than a year.

Speakers are used to emit audio signals that may come from music files or other audio files. Many pre-constructed computers come with external speakers. All come with internal speakers. Usually, the external speakers included are more than good enough for sound quality, whether you"re watching YouTube videos or playing a movie in your DVD player. There are people who prefer a little more bump in their audio output, however. Speakers are available in surround-sound systems that rival a home system. How loud you want your system to be is up to you. The higher-quality the sound system, the more expensive it will be.

Many computers now support Bluetooth technology. You can connect to Bluetooth-enabled speakers and set them up without the need for additional cables or connections!

You don"t have to pick all of these output devices for your computer system, but it is important to remember that monitors are output devices that let us see what we"re working on as we are working on it as well as to get a feel for what the finished product looks like.

Speakers are fun to shop for. They"re an audio output device allowing the transmission of sound files so the user can hear them. You can pick out how loud you want your system to be and find the sound package that works for you.

The widely-used input device in every computer is a keyboard. It contains keys that correspond to an alphabet, number, special character, or commands. A keyboard has 101 to 104 keys. However, nowadays, keyboards with 108 keys are also available. The layout of a keyboard is of QWERTY type. To input data into the computer using a keyboard, the user must press the correct keys on the keyboard. The computer will then process the data according to the instructions given.

A mouse is an input device with a small ball and three buttons on the top. It is also known as a pointing device. Using a mouse, the user can click on several icons available on the system and open files or applications. When the computer mouse is rolled across a flat surface, the screen senses its direction, and the cursor moves in the direction of the mouse.

A microphone is an input device that converts sound into electrical signals. A microphone is used to record voice, speech recognition, and non-acoustic purposes in a computer.

A bar code reader is an input device to read bar codes (codes given in light and dark lines). It is a type of optical scanner. A bar code passes a light source, and all the related information is displayed on the computer screen. It can be hand-held or a stationary scanner.

A scanner reads/scans images or text from a paper and transforms it into a digital signal. The information can be stored on the hard disk for manipulation or other purposes. Scanners can be of different types based on their purposes; for example, fingerprint scanners, 3-dimensional scanners, and image scanners.

OCR is like a scanner, but the process of scanning in OCR is different. It optically scans the text, character-wise, transforms it into machine-readable code, and stores it into the computer memory. The format used by OCR is predefined.

An OMR is a special type of input device used to check answers to objective-type questions. This type of scanner identifies the mark made using a pen or pencil in the OMR sheet. The answers are then matched to the predefined answer sheet and analyzed for correctness. OMR is extremely useful in automating the answer-sheet analysis of examinations.

A joystick is a pointing device that moves the cursor on the computer display. It has a stick connected at an angle with the base and a spherical ball on the bottom and top ends. It can move in all four directions. Joysticks are mainly used for playing games and in airplane cockpits.

Prices are very reasonable for basic projectors, however, a data projector capable of showing cinema films or sports footage in a bar are far more expensive.

These tiny mirrors are carefully in sync with the colour wheel, turning towards or away from the RGB light as and when it is needed, thousands of times per second. So, if part of the projected image requires no red light, they face away from the light when the colour wheel filter is allowing red light through.

Because the bulk of the action happens in the high-tech ink cartridges, they are priced quite highly in relation to the price of the actual printers (which are often very affordable).

A laser removes the negative charge from certain areas of the drum as it scans across it, creating a neutrally charged copy of the text/image to be printed.

Using a method called additive manufacturing, 3D objects are created by layering a material, layer by layer, from the ground up until the object is completed.

A 3D cutter is similar to a 2D cutter except it is capable of rotating and cutting at many angles. This means that 3D objects can have cuts made to all of its surfaces, unlike 2D cutters that can only cut into a flat 2D surface.

Speakers and headphones aren’t just for music, they also allow us to hear computer warning signals and other people when communicating via voice or video calls.

Actuators are the output devices responsible for creating real world movement. This could range from physically opening automatic shop doors to lowering the landing gears on a plane.

They are often used in a computerised control system, acting upon a signal sent by the microprocessor. Actuators include electric motors, pistons and pumps.

Monitors, commonly called as Visual Display Unit (VDU), are the main output device of a computer. It forms images from tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the number of pixels.

The CRT display is made up of small picture elements called pixels. The smaller the pixels, the better the image clarity or resolution. It takes more than one illuminated pixel to form a whole character, such as the letter ‘e’ in the word help.

A finite number of characters can be displayed on a screen at once. The screen can be divided into a series of character boxes - fixed location on the screen where a standard character can be placed. Most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically.

The flat-panel display refers to a class of video devices that have reduced volume, weight and power requirement in comparison to the CRT. You can hang them on walls or wear them on your wrists. Current uses of flat-panel displays include calculators, video games, monitors, laptop computer, and graphics display.

Emissive Displays − Emissive displays are devices that convert electrical energy into light. For example, plasma panel and LED (Light-Emitting Diodes).

Non-Emissive Displays − Non-emissive displays use optical effects to convert sunlight or light from some other source into graphics patterns. For example, LCD (Liquid-Crystal Device).

In the market, one of the most popular printers is Dot Matrix Printer. These printers are popular because of their ease of printing and economical price. Each character printed is in the form of pattern of dots and head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or 9*9) which come out to form a character which is why it is called Dot Matrix Printer.

Head is lying on a wheel and pins corresponding to characters are like petals of Daisy (flower) which is why it is called Daisy Wheel Printer. These printers are generally used for word-processing in offices that require a few letters to be sent here and there with very nice quality.

This printer is like a drum in shape hence it is called drum printer. The surface of the drum is divided into a number of tracks. Total tracks are equal to the size of the paper, i.e. for a paper width of 132 characters, drum will have 132 tracks. A character set is embossed on the track. Different character sets available in the market are 48 character set, 64 and 96 characters set. One rotation of drum prints one line. Drum printers are fast in speed and can print 300 to 2000 lines per minute.

Non-impact printers print the characters without using the ribbon. These printers print a complete page at a time, thus they are also called as Page Printers.

Inkjet printers are non-impact character printers based on a relatively new technology. They print characters by spraying small drops of ink onto paper. Inkjet printers produce high quality output with presentable features.

They make less noise because no hammering is done and these have many styles of printing modes available. Color printing is also possible. Some models of Inkjet printers can produce multiple copies of printing also.

Hard-copy is the tangible form of output. This output is printed on a paper by using printer or recorded on other durable surface such as microfilm. The hard copy is permanent and  is a relatively stable output. The most common hard-copy devices are:

Soft-copy is the electronic version of output data which is stored in a computer memory such as hard disk. It is not tangible and permanent form of output. This type of output can be displayed on the computer screen in visual form or can be listened as audio through speakers. The common soft-copy output devices are:

Printer is the commonly used output device used to produce or print the hard-copy of the output data on a paper. The output data may be text documents, images or graphics.  There are different types of printers used according to their mechanism and printing quality.

Impact printer is that printer which consists of a printer head or hammer. The printer head or hammer strikes against the paper through ink ribbon to print the images or characters on the paper. The common impact printers are;

Non-impact printer does not use hammers or printer heads to print. In fact, it employs other technologies like electro-static and ink-jet technologies for print operation other than directly striking on the paper. Non-impact printer produces less sound and  high quality images  than impact printer. It is faster than impact printer.  Non-impact printer is used to print text documents, graphics images in black and white as well as colour. The most common types of non-impact printers are:

It is a type of impact printer which prints one character at a time. It consists of a printer head which is allowed to strike the paper through ink ribbon. Since, the impression made by the head to the paper is in the form of dot, the print quality is determined by the number of dots made by the printer head pins. More are the number of pins on a head, higher is the printer resolution. The number of pins vary from 9 to 24.The speed of printer is measured in characters per second (cps) and it can vary from 200 to over 500 cps. Dot-matrix printers are inexpensive and have less operating cost. They are used in low quality applications like cash register, invoice copy etc.

It is also a type of impact printer which consist s of a mechanism that looks like a daisy flower and its printing arm resembles the petals of the flower, hence the name daisy wheel printer. It is commonly known as letter quality printer, because the print quality is better than that of the dot matrix printer. However, it has slower speed of about 100cps and can print only alphabets, numbers and special characters, but not graphics.

The dot-matrix printer and daisy wheel printer print one character at a time. That’s why they are also called characteror serial printers. However, the drum printer is a line printer that can print a whole line at a time. Hence, drum printer is faster than character printer. It consists of a special tractor-fed paper with pre-punched holes along each side that allows the printer to operate in a continuous high-speed. The speed may vary from 300 to 2000 lines per minute. Drum printer is designed for businesses where heavy printing is needed for a small amount of time. However, drum printer is considered to be expensive as compared to character printer.

Ink-jet printer uses a series of microscopic nozzles to spray liquid ink directly on the paper. It can print both black & white and colour pages. It produces very less sound while printing as compared to impact printer. The inkjet printer produces high quality print with a resolution of more than 600 dpi; hence the printing cost is relatively high. The printing speed is moderately high; however it takes more time to print multi-colour pages.  It is commonly used in homes, offices, small businesses, etc.

Laser jet printer uses the same basic technology as the conventional photo copier machine to print out the documents, images, etc. It produces a very high quality print and works very much faster than other printers discussed above. It can produce and store an entire page before it prints, hence it is also called page printer. The print resolution ranges between 300 to 2400 dpi. It can print  4-32 text-only pages per minute for microcomputers and up to 200 pages per minute for mainframes. The complex technology is used for printing operation in LaserJet printer, hence it is more expensive to buy and maintain than the other printers.

Plotter is another output device just like printer to draw vector graphics like high-resolution charts, graphs, maps, circuit diagram and other line based diagrams. It uses a series of different coloured (Cyan, Magenta, Yellow and black) pens to draw multiple, continuous and accurate lines. Since, the printing output must be more precise, accurate and minute details, it operates in much slower speed as compared to other printers. Plotters are used for high precision printing for Computer Aided Manufacturing ( CAM) and AUTOCAD ( computer assisted drafting).

Drum plotter consists of one or more pens mounted on a carriage that is placed horizontally across the drum and the printing paper is placed over the drum. The computer gives the plotting instruction to the drum to rotate it in both clockwise and anticlockwise direction.  Hence, the pen having different colour to produce multicolour design is allowed to move horizontally only, while the page moves vertically to computer to perform the print operation.

In flat-bed plotter, paper is placed stationary on the flatbed surface of the plotter. The pen of different colour is mounted on the carriage and this carriage is allowed to move horizontally, vertically, left and right to draw the lines. The flat-bed surface can be of varying sizes ranging from A4 size paper to more larger size , hence can be used for designing of ships, aircrafts, buildings and so on.

Microfilmis an output device which is in the form of a fiche. It records the computer output directly from the computer tape or cartridge. It is a high speed and low cost process to produce the copy of data on microfilm than that of paper printer. Normally, the film roll is 16 mm wide and the film image is 1/24 of the original document. Microfilm reader is used to read data/images from microfilm. Such microfilms are deployed for storing large amounts of archive data in a permanent film format for long periods of time.

The monitor or video display unit is the most common output device which displays the meaningful result as a soft-copy output. The monitor looks like a television screen on which the output is displayed and viewed either as colour or monochrome display. A monochrome screen uses only one colour to display text on contrasting background. The monitor can be used to show text, numbers, and graphics images. They come in many different sizes such as 14,15,17, 19, 1nd 21 inches. Aspect ratio and screen size are the two parameters which describe the size of the display. Aspect ratio is the ratio of the width and the height of the display screen, whereas the screen size is the length of two opposite corners of screen diagonally.

CRT monitor is based on CRT technology which consists of a vacuum tube having electron gun at one end and the florescent screen at other end. The high intensity rays of electrons are allowed to pass through the deflection coil which directs the beam towards the phosphor coated screen and strike on it to form images. Although, CRT monitors are almost obsolete after the advent of the flat screen like LCD or LED display, CRT were popularly used during the early days of the computing technology.

LCD monitor is based on liquid crystal display (LCD) technology. Unlike, CRT monitor which looks bulky and heavier, LCD screen is much lighter and compact. Its screen has flat surface. LCD screen consists of liquid crystal which is neither solid nor liquid, but it has a molecular property which behaves like crystalline. LCD screen contains multiple layers  which includes backlight, polarized filter, electrodes. In LCD display, CCFL (Code Cathode Fluorescent Lamp)  backlight is used which provides the light source to the display. The light from the backlight is passed through the vertically and horizontally polarized filters which convert the scattered light into a single axis beam. These beams are then passed through the TFT (Thin Film Transistor) and liquid crystal. There are thousands of small transistors which controls the intensity of the light. Each transistor controls single pixel and each pixel consists of three sub pixels: red, green, blue. The variation of light intensity on all the pixels helped to display texts, images on the screen.

LED monitor employs the same technology as the LCD screen. The only difference is that LED screen uses LED as the light source instead of CCFL backlight. The LED screen is lighter than LCD and also they are energy efficient.

Speaker is also a type of output device which is most commonly used in computer system. Speaker can convert the electrical signal into sound energy. Speaker receives audio inputs in the form of electrical signal and then coverts them into audible sound. The sound energy is measured in terms of frequency and amplitude. The low pitch and high pitch sounds are determined by the frequency. The audible frequency range produced by speaker is from 50 Hz to 5 kHz. The amplitude determines the increase and decrease of the volume level of sound energy. The higher is  the amplitude the, greater the sound volume and vice versa.

The widely-used input device in every computer is a keyboard. It contains keys that correspond to an alphabet, number, special character, or commands. A keyboard has 101 to 104 keys. However, nowadays, keyboards with 108 keys are also available. The layout of a keyboard is of QWERTY type. To input data into the computer using a keyboard, the user must press the correct keys on the keyboard. The computer will then process the data according to the instructions given.

A mouse is an input device with a small ball and three buttons on the top. It is also known as a pointing device. Using a mouse, the user can click on several icons available on the system and open files or applications. When the computer mouse is rolled across a flat surface, the screen senses its direction, and the cursor moves in the direction of the mouse.

A microphone is an input device that converts sound into electrical signals. A microphone is used to record voice, speech recognition, and non-acoustic purposes in a computer.

A bar code reader is an input device to read bar codes (codes given in light and dark lines). It is a type of optical scanner. A bar code passes a light source, and all the related information is displayed on the computer screen. It can be hand-held or a stationary scanner.

A scanner reads/scans images or text from a paper and transforms it into a digital signal. The information can be stored on the hard disk for manipulation or other purposes. Scanners can be of different types based on their purposes; for example, fingerprint scanners, 3-dimensional scanners, and image scanners.

OCR is like a scanner, but the process of scanning in OCR is different. It optically scans the text, character-wise, transforms it into machine-readable code, and stores it into the computer memory. The format used by OCR is predefined.

An OMR is a special type of input device used to check answers to objective-type questions. This type of scanner identifies the mark made using a pen or pencil in the OMR sheet. The answers are then matched to the predefined answer sheet and analyzed for correctness. OMR is extremely useful in automating the answer-sheet analysis of examinations.

A joystick is a pointing device that moves the cursor on the computer display. It has a stick connected at an angle with the base and a spherical ball on the bottom and top ends. It can move in all four directions. Joysticks are mainly used for playing games and in airplane cockpits.

There are many input devices such as a keyboard, mouse, webcam, microphone and more, which send information to a computer system for processing. An output device, like Monitor, printer and more, displays the result of processing generated by input devices. Input devices only work for giving input of data to the system, and output devices accept the output after processing of data from other devices.

One of the main differences between input and output devices is that input devices are ones that are used to give input to the system by the users, whereas output devices are those, which are used to reproduce the output signals for the user.

There are various devices that are used to accept input of data from user or output data generated by a computer; therefore, they are known as input devices or output devices. However, some devices are referred to as Input/output devices, as they can receive input and reproduce output.

For instance, as shown in the above image, a keyboard is an input device, sending an electrical signal to the computer system. A computer system accepts these signals as input, then translates them and produces or displays output to the user on the monitor as text or images. In the lower half of the image, it is also shown that after processing, the computer sends data or output to the printer. Then, once the computer sends output to the printer, it is printed onto the piece of paper that is also considered output.

An input device can receive instructions from users or forward information to another device, but it is not able to accept data from another system. After receiving input, it translates these data into the electrical signals in binary code, which cannot be understandable by humans, and only a digital computer can understand it. There are many examples of input devices, which are discussed below:

Output devices are the section of a computer device that receives data from another device and produces output with the information. Although it cannot send data to another device, it has the ability to forward data from a computer to another computer system. It functions to take data from input devices and translate the digitized signals into a form that can be understandable by users. There are various examples of output devices; some are discussed below:

Monitor: A monitor is a piece of computer hardware that accepts data from a computer (output) and displays it on the system screen through the computer"s video card. Monitors have the ability to display information at a much higher resolution. Additionally, these are much like televisions and also known as video screen, display, video display terminal, or video display unit.

Speakers: The most common output devices, speakers accept sound data from a computer and play the sounds for users to hear. Although speakers can be used with any type of sound system, some speakers are manufactured only for computers. It is a device that cannot receive sound generated by users as well as refer that sound to another device. The main objective of the speakers is to produce sound or audio output for the listener.

Projector: A projector is an output device that accepts data from a computer (output) and projects that data or information as a picture onto a wall or screen or any large surface. It does not have the ability to receive data from a user and also not capable of sending that data to another device. When you are showing video or images to a large group of people, a projector is more beneficial to use instead of a monitor because it displays data on a large surface that can be visible to a large number of people clearly.

An input/output device has the ability to accept data from users or another device (input), as well as forward data to another device (output). Some examples of input/output devices are discussed below:

CD-RW drive and DVD-RW drive: These drives functions for accepting data from a computer as an input to copy onto a writable CD or DVD. And, this data contained on a CD or DVD is sent by the drive to the computer.

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Hard-copy is the tangible form of output. This output is printed on a paper by using printer or recorded on other durable surface such as microfilm. The hard copy is permanent and  is a relatively stable output. The most common hard-copy devices are:

Soft-copy is the electronic version of output data which is stored in a computer memory such as hard disk. It is not tangible and permanent form of output. This type of output can be displayed on the computer screen in visual form or can be listened as audio through speakers. The common soft-copy output devices are:

Printer is the commonly used output device used to produce or print the hard-copy of the output data on a paper. The output data may be text documents, images or graphics.  There are different types of printers used according to their mechanism and printing quality.

Impact printer is that printer which consists of a printer head or hammer. The printer head or hammer strikes against the paper through ink ribbon to print the images or characters on the paper. The common impact printers are;

Non-impact printer does not use hammers or printer heads to print. In fact, it employs other technologies like electro-static and ink-jet technologies for print operation other than directly striking on the paper. Non-impact printer produces less sound and  high quality images  than impact printer. It is faster than impact printer.  Non-impact printer is used to print text documents, graphics images in black and white as well as colour. The most common types of non-impact printers are:

It is a type of impact printer which prints one character at a time. It consists of a printer head which is allowed to strike the paper through ink ribbon. Since, the impression made by the head to the paper is in the form of dot, the print quality is determined by the number of dots made by the printer head pins. More are the number of pins on a head, higher is the printer resolution. The number of pins vary from 9 to 24.The speed of printer is measured in characters per second (cps) and it can vary from 200 to over 500 cps. Dot-matrix printers are inexpensive and have less operating cost. They are used in low quality applications like cash register, invoice copy etc.

It is also a type of impact printer which consist s of a mechanism that looks like a daisy flower and its printing arm resembles the petals of the flower, hence the name daisy wheel printer. It is commonly known as letter quality printer, because the print quality is better than that of the dot matrix printer. However, it has slower speed of about 100cps and can print only alphabets, numbers and special characters, but not graphics.

The dot-matrix printer and daisy wheel printer print one character at a time. That’s why they are also called characteror serial printers. However, the drum printer is a line printer that can print a whole line at a time. Hence, drum printer is faster than character printer. It consists of a special tractor-fed paper with pre-punched holes along each side that allows the printer to operate in a continuous high-speed. The speed may vary from 300 to 2000 lines per minute. Drum printer is designed for businesses where heavy printing is needed for a small amount of time. However, drum printer is considered to be expensive as compared to character printer.

Ink-jet printer uses a series of microscopic nozzles to spray liquid ink directly on the paper. It can print both black & white and colour pages. It produces very less sound while printing as compared to impact printer. The inkjet printer produces high quality print with a resolution of more than 600 dpi; hence the printing cost is relatively high. The printing speed is moderately high; however it takes more time to print multi-colour pages.  It is commonly used in homes, offices, small businesses, etc.

Laser jet printer uses the same basic technology as the conventional photo copier machine to print out the documents, images, etc. It produces a very high quality print and works very much faster than other printers discussed above. It can produce and store an entire page before it prints, hence it is also called page printer. The print resolution ranges between 300 to 2400 dpi. It can print  4-32 text-only pages per minute for microcomputers and up to 200 pages per minute for mainframes. The complex technology is used for printing operation in LaserJet printer, hence it is more expensive to buy and maintain than the other printers.

Plotter is another output device just like printer to draw vector graphics like high-resolution charts, graphs, maps, circuit diagram and other line based diagrams. It uses a series of different coloured (Cyan, Magenta, Yellow and black) pens to draw multiple, continuous and accurate lines. Since, the printing output must be more precise, accurate and minute details, it operates in much slower speed as compared to other printers. Plotters are used for high precision printing for Computer Aided Manufacturing ( CAM) and AUTOCAD ( computer assisted drafting).

Drum plotter consists of one or more pens mounted on a carriage that is placed horizontally across the drum and the printing paper is placed over the drum. The computer gives the plotting instruction to the drum to rotate it in both clockwise and anticlockwise direction.  Hence, the pen having different colour to produce multicolour design is allowed to move horizontally only, while the page moves vertically to computer to perform the print operation.

In flat-bed plotter, paper is placed stationary on the flatbed surface of the plotter. The pen of different colour is mounted on the carriage and this carriage is allowed to move horizontally, vertically, left and right to draw the lines. The flat-bed surface can be of varying sizes ranging from A4 size paper to more larger size , hence can be used for designing of ships, aircrafts, buildings and so on.

Microfilmis an output device which is in the form of a fiche. It records the computer output directly from the computer tape or cartridge. It is a high speed and low cost process to produce the copy of data on microfilm than that of paper printer. Normally, the film roll is 16 mm wide and the film image is 1/24 of the original document. Microfilm reader is used to read data/images from microfilm. Such microfilms are deployed for storing large amounts of archive data in a permanent film format for long periods of time.

The monitor or video display unit is the most common output device which displays the meaningful result as a soft-copy output. The monitor looks like a television screen on which the output is displayed and viewed either as colour or monochrome display. A monochrome screen uses only one colour to display text on contrasting background. The monitor can be used to show text, numbers, and graphics images. They come in many different sizes such as 14,15,17, 19, 1nd 21 inches. Aspect ratio and screen size are the two parameters which describe the size of the display. Aspect ratio is the ratio of the width and the height of the display screen, whereas the screen size is the length of two opposite corners of screen diagonally.

CRT monitor is based on CRT technology which consists of a vacuum tube having electron gun at one end and the florescent screen at other end. The high intensity rays of electrons are allowed to pass through the deflection coil which directs the beam towards the phosphor coated screen and strike on it to form images. Although, CRT monitors are almost obsolete after the advent of the flat screen like LCD or LED display, CRT were popularly used during the early days of the computing technology.

LCD monitor is based on liquid crystal display (LCD) technology. Unlike, CRT monitor which looks bulky and heavier, LCD screen is much lighter and compact. Its screen has flat surface. LCD screen consists of liquid crystal which is neither solid nor liquid, but it has a molecular property which behaves like crystalline. LCD screen contains multiple layers  which includes backlight, polarized filter, electrodes. In LCD display, CCFL (Code Cathode Fluorescent Lamp)  backlight is used which provides the light source to the display. The light from the backlight is passed through the vertically and horizontally polarized filters which convert the scattered light into a single axis beam. These beams are then passed through the TFT (Thin Film Transistor) and liquid crystal. There are thousands of small transistors which controls the intensity of the light. Each transistor controls single pixel and each pixel consists of three sub pixels: red, green, blue. The variation of light intensity on all the pixels helped to display texts, images on the screen.

LED monitor employs the same technology as the LCD screen. The only difference is that LED screen uses LED as the light source instead of CCFL backlight. The LED screen is lighter than LCD and also they are energy efficient.

Speaker is also a type of output device which is most commonly used in computer system. Speaker can convert the electrical signal into sound energy. Speaker receives audio inputs in the form of electrical signal and then coverts them into audible sound. The sound energy is measured in terms of frequency and amplitude. The low pitch and high pitch sounds are determined by the frequency. The audible frequency range produced by speaker is from 50 Hz to 5 kHz. The amplitude determines the increase and decrease of the volume level of sound energy. The higher is  the amplitude the, greater the sound volume and vice versa.