SQL
SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Ted Codd in the early 1970s. This version, initially called "SEQUEL" ("Structured English Query Language"), was designed to manipulate and retrieve data stored in IBM's original quasi-relational database management system, System R, which a group at IBM San Jose Research Laboratory had developed during the 1970s.
TimeClock Plus
Until 2005, the software used a Dbase compatible database, but from version 5.0, it changed to Microsoft SQL. In 2006 the first web version was released as a simple, scaled down version of 5.0 for Windows. This removed the necessity of a client installation and also made the system available to Macintosh users for the first time. In 2008 a complete web version of 5.0 for Windows was introduced.