PC Paintbrush

PC Paintbrush is graphics editing software created by the ZSoft Corporation in 1984 for computers running the MS-DOS operating system.

It was originally developed as a response to the first paintbrush program for the IBM PC, PCPaint, which had been released the prior year by Mouse Systems, the company responsible for bringing the mouse to the IBM PC for the first time.

In 1984, Mouse Systems had released PCPaint to compete with Apple Paint on the Apple II computer and was already positioned to compete with MacPaint on Apple Computer's new Macintosh platform. Unlike MacPaint, PCPaint enabled users to work in color.

When Paintbrush was released the following year, PCPaint had already added 16-color support for the PC's 64-color Enhanced Graphics Adapter (EGA), and Paintbrush followed with the PC's advantage of EGA support as well. (The EGA supported 64 colors, of which any 16 could be on the screen at a time in normal use.)

Also following the lead of Mouse Systems and PCPaint, one of the first pieces of software on the PC to use a computer mouse pointing device, the earliest versions of Paintbrush were distributed by Microsoft, with a mouse included. Both Microsoft and their competitor, Mouse Systems, bundled their mice with Mouse Systems' PCPaint in 1984. At Christmas 1984, amidst record sales volumes in the home computer market, Microsoft had created a "sidecar" bundle for the PCjr, complete with their mouse, but with their competitor's product, PCPaint. With the release of Paintbrush the following year, Microsoft no longer needed to sell the software of their competitor in the PC mouse hardware market in order to have the same market advantage.

Microsoft's mechanical mice outsold Mouse Systems' optical mice after a few years, but PCPaint outsold Paintbrush until the late 1980s.

Unlike most other applications before and since, Paintbrush version numbers were recorded with Roman numerals.