Input devices are essential in order to use a computer. These devices allow users to interact with the applications that the computer displays. Without input devices, the computer would be nothing more than a screen that displays something random and of little use. There are many different types of input devices that all allow us to interact in different ways.
A keyboard consists of a series of keys that can be pressed to input commands or letters. These are used to write documents but can be used to navigate user interfaces in lieu of a mouse.
A mouse consists of a ball or laser that tracks the movement of the device. The computer is able to register the movement of the mouse and translate it as movement of the cursor on the screen. A mouse also contain buttons that allow the user to select objects, move windows or open applications. Many also include a scrolling wheel to allow for scrolling through long documents or Web pages.
These devices work like a standard mouse except the users rolls a ball inside a base rather than moving the device across the table top. Many users prefer a trackball to a mouse, because it involves less wrist movement, reducing repetitive-motion issues.
This is a device typically found on laptop computers. It works like a mouse or trackball, except it's a flat panel you move your finger across. The motion of your finger registers as cursor movement on the screen. Many touchpads now enable gestures to scroll through documents or zoom in on a photo. Buttons are typically below the touchpad.
These devices are used like a piece of paper and a pencil. These allow artists to draw more naturally in a graphics application. They have a stylus that looks like a plastic pencil that you can use to draw on a flat panel. The device will register the pressure of the user's hand to draw lighter or darker lines on screen. Many even have erasers on the back that allow you to erase mistakes with the stylus.
These devices double as an output and input device. They display the computer environment on screen, and allow a user to manipulate and interface with it just by touching the screen. These can take the place of a mouse and even a keyboard if a virtual keyboard application is installed.
These devices are primarily used for computer gaming. They consist of a stick on a base with various buttons that all have different functions. It operates similar to a yoke on an aircraft, making them suitable for flight simulators.
These devices allow a user to input a photograph or document into the computer. By placing a piece of media in a scanner, you can create an image file that can be opened and manipulated on the computer.
This is a device used to input voice data and sound. You hold the microphone up to a source, most likely a person's mouth, and it registers the sounds and inputs them into audio recording applications. This will let you do many things, from recording a song to talking to someone on Skype.
This is a small video camera that takes video and inputs it into the computer. These allow you to record and send small videos or have a video chat with someone over the Internet.