Keyboard (computer)

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A QWERTY computer keyboard in US layout.

A computer keyboard is an input device that allows a person to enter symbols like letters and numbers into a computer. It is the main input device for most computers.

There are different types of keyboards, and different arrangements of keys. The most popular is the QWERTY design, which is based on typewriter keyboards. The QWERTY design was made so the most frequently used letters would not jam a mechanical typewriter. Now typewriters are rare but the design stayed because people were used to it. An ergonomic keyboard is made to be easier for people to use, without hurting their hands or arms. The keyboard can type letters, numbers and punctuation, and also lets you control the computer, using special keys like the START button, and the arrow keys. A Dvorak keyboard is an alternative layout.

A keyboard is most commonly attached to a computer via USB port. Some use Bluetooth instead.

Keystroke logging is capturing a record of each key that is pressed. Keystroke logging can be used to measure employee activity. Hackers can also use keystroke logging. Scientists discovered that most keyboards give off electromagnetic radiation that can be used to tell which keys have been pressed. Spies could determine what has been typed by remotely sensing such signals.[1][2]

Researchers are studying if keyboards can spread diseases. Some keyboards were found to contain five times more germs than a toilet seat.[3]

Characters available on a keyboard are generally those of the local language, although ASCII characters tend to be available everywhere.

Characters on an English language keyboard are 1,2,3,4,5,6,7,8,9,0,-,=,q,w,e,r,t,y,u,i,o,p,[,],a,s,d,f,g,h,j,k,l,;,',#,\,z,x,c,v,b,n,m,.,/,!,",£,$,%,^,&,*,(,),_,+,Q,W,E,R,T,Y,U,I,O,P,{,},A,S,D,F,G,H,J,K,L,:,@,~,|,Z,X,C,V,B,N,M,<,>,? and some keys are not for a character.

Related pages[change | change source]

References[change | change source]

  1. Lasewww.epfl.ch
  2. Newscientist.com
  3. http://abcnews.go.com/Health/Germs/story?id=4774746&page=1