**Computer
science**
Computer science, or computing science,
is the study of the theoretical foundations of information
and computation and their implementation and application
in computer systems.[1][2][3] Computer science has many
sub-fields; some emphasize the computation of specific results
(such as computer graphics), while others (such as computational
complexity theory) relate to properties of computational
problems. Still others focus on the challenges in implementing
computations. For example, programming language theory studies
approaches to describing computations, while computer programming
applies specific programming languages to solve specific
computational problems.
The history of computer science predates
the invention of the modern digital computer by many years.
Machines for calculating fixed numerical tasks have existed
since antiquity, such as the abacus. Wilhelm Schickard built
the first mechanical calculator in 1623.[4] Charles Babbage
designed a difference engine in Victorian times[5], and
around 1900 the IBM corporation sold punch-card machines[6].
However all of these machines were constrained to perform
a single task, or at best, some subset of all possible tasks. |