WordPerfect (WP) is a word processing application, now owned by Corel, with a long history on multiple personal computer platforms. At the height of its popularity in the 1980s and early 1990s, it was the dominant player in the word processor market, displacing the prior market leader WordStar. It was originally developed under contract at Brigham Young University for use on a Data General minicomputer in the late 1970s. The authors retained the rights to the program, forming the Utah-based Satellite Software International (SSI) in 1979 to sell it; the program first came to market under the name SSI*WP in March 1980. It then moved to the MS-DOS operating system in 1982, by which time the name WordPerfect was in use, and several greatly updated versions quickly followed. The application's feature list was considerably more advanced than its main competition WordStar, an established program based on the operating system CP/M that failed to transition successfully onto MS-DOS, which replaced CP/M. Satellite Software International changed its name to WordPerfect Corporation in 1985. WordPerfect gained praise for its "look of sparseness" and clean display. It rapidly displaced most other systems, especially after the 4.2 release in 1986, and it became the standard in the DOS market by version 5.1 in 1989. Its early popularity was based partly on its availability for a wide variety of computers and operating systems, and also partly because of extensive, no-cost support, with "hold jockeys" entertaining users while waiting on the phone. Its dominant position ended after a failed release for Microsoft Windows due to Microsoft not initially sharing its Windows Application Programming Interface (API) specifications causing the application to be slow. After receiving the Windows APIs, there was a long delay in reprogramming before introducing an improved version. Microsoft Word had been introduced at the same time as WordPerfect's first attempt, and Word took over the market due to being faster, helped by aggressive bundling deals that ultimately produced Microsoft Office. WordPerfect was no longer a popular standard by the mid-1990s. WordPerfect Corporation was sold to Novell in 1994, which then sold the product to Corel in 1996. Corel has made regular releases to the product since then, often in the form of office suites under the WordPerfect name that include the Quattro Pro spreadsheet, the Presentations slides formatter, and other applications. The common filename extension of WordPerfect document files is .wpd. Older versions of WordPerfect