What a computer can do

Robert P. Webber, Scott McElfresh, Longwood University
 

What defines a computer? 

How does a computer differ from a calculator, for instance?

At its heart, a computer is a calculating device.  It accepts information, does computations, stores data, and sends output to the user.  Some computers are built to perform only one task, but most can be programmed.  A programmable calculator is a computer, for example.

 

Basic Operations

 
There is a very small set of basic operations that a computer knows how to do.
Anything else must be programmed.

Can computers think? 

The answer to that question is not obvious.  Even philosophers do not agree on what it means to “think.”  Alan Turing, a 20th century British mathematician, proposed a test to determine if a machine can think.  Suppose a room has two screens, with a human behind one screen and a machine behind the other.  You do not know which is which, but you can ask either one any question you like.  If you cannot distinguish the human from the machine, then the machine is able to think.


This test is still used as the benchmark for artificial intelligence.  So far, no computer has passed the Turing test, although it may be difficult for a novice (or even an expert) to determine which is the computer.  There is a famous program called Eliza (you can find it on the Internet) that purports to be psychiatrist.  It seems eerily human as it guides a person through a therapy session.

Credits and licensing

This article is by Robert P. Webber and Scott McElfresh, licensed under a Creative Commons BY-SA 3.0 license.

Version 2015-Aug-22 18:30