Cornerstone was a relational database that supported Microsoft DOS. It was primarily marketed for commercial data management. Cornerstone was an early example of a database system with complex text parsing, and could accurately interpret input like “next Wednesday”. Cornerstone could be used by non-programmers, and included features such as a menu-driven interface, context-specific help, and command completion. It also supported variable-length and multi-valued fields, and could store text fields with up to 4,000 characters (compared to many of its contemporaries, which supported 255 characters), with full searching.
Cornerstone was created in 1985 by Infocom, a software company that primarily sold video games. The key developers of Cornerstone were Brian Berkowitz and Richard Ilson, who joined Infocom to build its first database software. It was neither a derivative system nor did it stem from an academic project. Cornerstone has not gone through any name changes. Infocom was acquired by Activision in 1986, and when Cornerstone was closed down in 1989, it had sold about 10,000 copies.