interface - Why are keyboards still the predominant input device?

While reading about the history of the computer keyboard I was a little surprised to hear that it is still the primary interface between humans and computers...

Despite the development of alternative input devices, such as the mouse, touchscreen, pen devices, character recognition and voice recognition, the keyboard remains the most commonly used device for direct (human) input of alphanumeric data into computers.

So why are computer keyboards still the most used input device?

extra credit: Will any emerging technologies be able to dethrone the keyboard as a primary input device?

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I learned quite a bit about why the computer mouse has been far superior to other pointing devices in another question on UX StackExchange and am hoping to have another great discussion on the factors that lead to the success of the computer keyboard as our primary input device.

Answer

Because of:

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  Familiarity: Everyone has more or less learned to use it and a lot of users don't even need to take a look at at individual keys to type. Although not physically, it's present and has the same layout across devices.

  
  


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  Usefulness: You can perform an incredible HUGE variety of task just with a keyboard.

  
  


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  Accessibility: It provides an accessible interface even for people capable of very little or impaired movement. For people with impaired vision there are some low vision keyboards available.

  
  
  


• Learning curve: You don't need previous experience or any particular ability to start using it and get the things done.


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  Privacy: Compared with other methods as Speech Recognition, you can type anything without worrying about everyone around getting the content of your message.

  
  


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  Historical: It has been the first easy-to-use, "effortless" and efficient input device for computers, which led it to become the main input device for them. It's the heir of the typewriter, which have made the transition minimal or nonexistent.

  
  


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  Variety: You can choose between different keyboards types for different usages or personal preference. You get from standard models to ergonomic , flexible, for gaming, mini, mechanical, multimedia, spill resistance, backlit, etc. And it seems that there is no reason for not expecting new types to be developed in the future, which could probably extend and/or improve its capabilities.

  
  
  


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  Speed + Response + Feedback : For some applications (like Gaming) you need to be a able to react as quick and accurately as possible and keyboards provide this feature because of the minimal distance and effort needed to press a key plus the almost instant time lapse perception between key pressing action an its response on the system.
  _Additionaly, it provides you a physical feedback which is relevant to UX (even more for the people who needs to look at the keyboard to type). It also provides audible feedback which is positive unless you or your roommates/coworkers get annoyed by the key pressing sound.

  
  


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  Lack of all-purpose competitors: They could be better in some fields and for some specific applications, but they don't have, at least for now, neither the precision nor the amount of capabilities that a standard keyboard offers.