The Pocket PC was an evolution from prior calculator-sized computers. Keystroke-programmable calculators which could do simple business and scientific applications were available by the 1970s. In 1982, Hewlett Packard's HP-75 incorporated a 1-line text display, an alphanumeric keyboard, HP BASIC language and some basic PDA abilities. The HP 95LX, HP 100LX and HP 200LX series packed a PC-compatible MS-DOS computer with graphics display and QWERTY keyboard into a palmtop format. The HP OmniGo 100 and 120 used a pen and graphics interface on DOS-based PC/GEOS, but was not widely sold in the United States. The HP 300LX built a palmtop computer on the Windows CE operating system.