The rise of computers dates back to ancient times and to the development of mathamatics and calculators.  Computers began taking shape in the late 1800's-early 1900's.  They were once the size of an entire room and required great amounts of money to fund and purchase.  Due to the enormous size and cost of computers, the idea of personal computers did not begin to take shape until the 1960-70's.  It is from this point that people started looking into creating more "portable computers" for home use.