Computer Basics: What Is an Output Device? 10 Examples
What Is an Output Device?
An output device is a piece of computer hardware that receives data from a computer and then translates that data into another form. That form may be audio, visual, textual, or hard copy such as a printed document.
The key distinction between an input device and an output device is that an input device sends data to the computer, whereas an output device receives data from the computer.
For example, using a microphone to record a podcast is an example of using an input device. Listening to the recorded podcast through a connected speaker is an example of using an output device. Both output and input devices are examples of auxiliary or peripheral devices.
Analyzing the Functionality of a Device
There are four different categories of output device: visual, data, print, and sound. Each output device example has a specific history, so here I cover specifically how each device works, when it became a part of technology history, popular brands on the market selling the device, and a fun fact.
For more information about input devices, check out my article "Computer Basics: 10 Examples of Input Devices."
10 Examples of Output Devices
- Computer Speakers
- Sound Card
- Video Card
- Braille Reader
- Speech-Generating Device
Function: A monitor consists of a screen, circuitry, a power supply, buttons to adjust screen settings, and a casing that contains all of these components. A monitor displays data from a computer onto a screen so the user can interact with the data via a digital interface.
Popular Brands: Acer, Alienware, Apple, Asus, Dell, HP, LG, Lenovo, Samsung
Origin Story: The first monitors used the same technology as early televisions, relying on a cathode ray tube and a fluorescent screen. This technology was first utilized for computer monitors in 1965 in the Uniscope 300 machine, which had a built-in CRT display. CRT display lights up a series of dots with a beam on an active part of the screen. This resulted in a maximum resolution of 1600 by 1200 pixels. LCD (liquid crystal display) entered the market in 2000 and outsold CRT monitors in 2007. Nowadays, monitors incorporate flat display technology. Plasma monitors are brighter than both CRT and LCD and function by illuminating tiny charged gas bubbles, or plasma, in the screen.
Fun Fact: VDT (video display terminal) and VDU (video display unit) are alternative names for monitors.
Function: The function of a printer is to create a copy of whatever is sent from the computer to the printer. Printers take electronic data sent from a computer and generate a hard copy.
Popular Brands: Brother, Canon, Epson
Origin Story: Photocopying, also known as xerography, is the origin-technology of modern-day printing and was invented in 1938 by Chester S. Carlson of Queens, New York.
The first inkjet printer was developed in 1951. There are many different types of printers, with inkjet and laser printers being two of the most common. Modern printers usually connect to a computer with a USB cable or via Wi-Fi.
Fun Fact: A plotter, which is also a type of print output device, is a similar type of hardware device to a printer. Unlike a printer, however, plotters use writing tools, such as pen, pencil, marker, to draw lines. Designed to use vector graphics, plotters were once commonly employed for computer-aided design, but have now been largely replaced by wide-format printers.
Function: Headphones output audio from a computer through two individual headphones for a single listener. Also known as earphones, headphones allow you to listen to audio without disrupting other people in the vicinity.
Popular Brands: Sennheiser, JBL, Bose, Sony, Skullcandy
Origin Story: There’s no single figure who invented headphones, but the use of headphones stems from the military. Nathaniel Baldwin of Utah submitted a headphone prototype to the U.S. Navy in 1910, which was adopted some years after by Naval radio operators. Koss Corporation then created the first commercial stereo headphones in 1958. Nowadays, headphones come in all shapes and sizes, from basic earbuds to the traditional style with padding around the earpieces and a connecting band that fits over the user's head.
Fun Fact: Headphones were popularized for mainstream use in 1979 by Sony Walkman.
4. Computer Speakers
Function: Computer speakers are hardware devices that transform the signal from the computer's sound card into audio. Speakers create sound using internal amplifiers that vibrate at different frequencies according to data from the computer. This produces sound.
Popular Brands: Audioengine, Logitech, Razer, Harman
Origin Story: Speakers are essential if you want a louder sound, surround sound, fuller bass, or just higher quality audio. The first internal computer speaker (a speaker inside the chassis of a laptop) was created in 1981 by IBM. External computer speakers began to appear in stores in the early 1990s when computer gaming, digital music, and other forms of media became popular. Some computer speakers are wireless nowadays, connecting to the computer via Bluetooth.
Fun Fact: You can turn your speakers (or headphones!) into a microphone. The difference between computer speakers and a microphone is that the frequency of the vibration originates from external sounds rather than data from a computer.
Function: As its name suggests, this output device "projects" computer images or video onto a wall or screen.
Popular Brands: BenQ, Sony, Optoma, Epson
Origin Story: Originally, projectors weren’t an output device. Projectors were first created and used in late 19th-century France. Throughout history, biunial lanterns were used to project ink on glass by photographers, lecturers, and magicians. A biunial lantern is a lantern with projection capabilities. "Biunial" means combining two things into one, so a biunial lantern is a directional lantern and a glass slide with a print on it for projecting.
In the early 1920s, filmstrips were used to show “films” in classrooms. Turning the knob allowed teachers to stop on specific slides. Clear film copies for projectors weren’t invented until the 1960s, and 3M became the leading producer in clear film and projectors.
The data projector was invented in 1980. This is the first year it was considered an “output device.” The data projector was the first rendition of the projector that was closest to modern-day. Using a single cathode ray tube (CRT), the first data projector projected only monochromatically.
Nowadays, projectors are typically used for presentations, watching movies, or as a teaching aid, as they enable an entire roomful of people to see images generated by a single computer. Modern projectors usually connect to the computer via an HDMI (high-definition multimedia) cable or VGA (video graphics array) cable.
Fun Fact: 3D projectors are designed to project two images of the same thing from different angles at the same time. Wearing 3D glasses, the viewer can see a 3D projection composed of multiple superimposed images.
6. GPS (Global Positioning System)
Function: GPS is a radio-based navigation system that’s composed of a sender computer and a receiver. The sender broadcasts signals to 24 satellites that ping to the sender the exact location of the sender computer in the form of latitude and longitude coordinates. The satellites use microwave signals to “talk” to the GPS, giving information on location, vehicle speed, and a number of other pieces of data.
Popular Brands: Magellan, Garmin, TomTom
Origin Story: A Soviet-era technology, GPS was originally used in the 1960s to track U.S. submarines carrying nuclear missiles. The Department of Defense deployed more satellites to bolster the burgeoning navigation system. By 1993, 24 satellites were in orbit and GPS was used broadly across the world in agriculture, aviation, the military, athletics, science, and the list goes on.
Fun Fact: Until May 1st, 2000, high-quality GPS signals were confined for use by the government.
7. Sound Card
Function: The sound card controls the output of sound signals, enabling devices like speakers and headphones to work. The sound card is known as an expansion card, which means it can be added to the motherboard. Although a sound card is not essential to a computer's basic functionality, you need one if you wish to play games, watch movies, listen to music, and use audio and video conferencing.
Popular Brands: Audigy, ASUS, Creative, EVGA
Origin Story: The first sound card was invented by Sherwin Gooch in 1972 and was used in PLATO systems (Programmed Logic for Automatic Teaching Operations). PLATO was the first computer-assisted learning system in widespread use. It wasn't until 1988 that sound cards were widely used in PCs.
When computer data is sent through a sound card, it is sent to the card digitally. The sound card then translates the digital information (in the form of binary, or 0s and 1s) into analog information: vibrations, output in the form of sound.
Fun Fact: The popularization of sound cards originated in the gaming realm. Sierra Entertainment, a gaming platform, began supporting add-ons like sound cards and this enabled the sound card industry to grow without being an underground solution to a growing issue: shallow sound while gaming.
8. Video Card
Function: As with the sound card, the video card is an expansion card that slots into the motherboard. The video card processes images and video, enabling visuals to be seen on a display. Most computers have basic video and graphics capabilities built into the computer's motherboard, but for faster, more detailed graphics, a video card is required.
Popular Brands: NIVIDIA, ASUS, MSI, EVGA
Origin Story: Video cards are also known as GPUs or graphics processing units. Before modern-day GPUs, IBM introduced the MDA (monochrome display adapter). The MDA supported visuals such as text and lines for uses such as drafting but didn't offer any graphical experiences.
In order to increase the functionality of the burgeoning computing technology, Hercules Computer Technology invented the Hercules Graphics Card, which integrated with the MDA to offer a bitmapped (or "rasterized," or pixelated), graphics experience. From the 1990s on, graphics technology was increasingly like modern-day graphics cards and has increased in graphic quality and speed significantly since then.
Fun Fact: Video cards can work in both 2D images and 3D images. Images like browsers, computer desktops, and PDFs are considered 2D images, whereas computer games are considered 3D.
9. Braille Reader
Function: A braille reader is a peripheral device that enables a blind person to read text displayed on a computer monitor. The text is sent by the computer to the device, where it is translated into a braille format and made readable by pushing rounded pins up through a flat surface. Braille readers are also called braille displays and come in various sizes. Braille readers come in the form of separate devices from a keyboard or as part of a keyboard. Most use piezoelectric technology, or electricity generated by mechanical stress, to create a single line of text at a time in the form of raised bumps.
This was the case until late 2018 when Blitlab proposed an electronic solution to the limited capabilities of braille readers. Blitlab, upon its release, will allow the visually impaired to use the internet and read books and newspapers more independently. The technology is still in development. The device will cost only around $500, which is little compared to traditional braille readers, which cost around $5,000 to $11,000.
Popular Brands: ALVA, Handy Tech, Freedom Scientific, BrailleNote
Origin Story: Braille is a 63 character alphabet invented in 1824 by Louis Braille. Braille was embossed on paper and other materials for decades before braille reader technology was invented. The first braille output technology was patented in 1975 by the Schönherr Company, and braille reader technology has evolved slowly since.
Fun Fact: Blitlab is the first tablet-style braille reader technology that will utilize a perforated glass screen that raises bumps as the computer reads the text from websites and translates it to braille.
10. Speech-Generating Device (SGD)
Function: SGDs, also known as voice output communication aids, generate text to speech. A user types something and when the command is sent, the SGD reads the sentence out loud.
Popular Brands: DynaVox, Luminaud, ZYGO Industries, Inc.
Origin Story: The first version of the SGD used print output. The “patient-operated selector mechanism,” or POSSUM, found symbols on a display and illuminated them for the reader. In the 1980s Dynavox was formed by students from Carnegie Mellon University with the goal to make an effective SGD for a young woman with cerebral palsy. This resulted in the invention of the EyeTyper, a device that allowed the user to spell with their eyes that would then be spoken.
Fun Fact: The most famous use of an SGD was by Stephen Hawking. Hawking was an astrophysicist with Lou Gehrig’s disease (also known as ALS). Lou Gehrig’s disease slowly deteriorates nerves in the spine and brain that results in gradual loss of muscle control. This often includes the ability to speak.
Other Output Device Examples
- Computer Output Microfilm (COM, or Microfiche): COM is used to create a film image of the page sent from a computer.
- Plotter: A plotter interprets vector graphics files and draws lines between points.
- Television: A television (TV) is fed video and sound data which is output to the user in the form of synchronized sound and pictures.
Devices That Both Output and Input Data
- Modem: A modem sends and receives information over a telephone line or cables.
- Touch Screen: Touch screens accept input in the form of touch and display the output from the computer.
- Network Card (NIC): A network card is an expansion card for a computer that allows the device to connect to the network or internet.
Output Device Knowledge: An Evolving Topic
The variety and complexity of output devices evolve with technology. Conceptually output devices have existed for decades. The biunial lantern, for example, sufficed in lieu of a more advanced option for projecting pictures; most output devices (like projectors) as they are known today didn't come into widespread use until the popularization of computer use at home in the 1980s.
Please leave questions, comments, and concerns in the comments below! I'd love to hear about your experiences with different output devices.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2019 Paul Goodman