Paradox is a relational database management system currently published by Corel Corporation. It was originally released for MS-DOS by Ansa Software, and then updated by Borland after it bought the company. In mid 1991 Borland began the process to acquire Ashton-Tate and its competing dBase product line; A Windows version was planned for release by Borland in 1992, but was delayed until January 1993, by which time Microsoft's Access for Windows was available. It was last updated in 2009. Paradox for DOS Paradox for DOS was a relational database management system originally written by Richard Schwartz and Robert Shostak, and released by their Belmont, California-based company Ansa Software in 1985. The New York Times described it as "among the first of an emerging generation of software making extensive use of artificial intelligence techniques," and noted that Paradox could read the competing Ashton Tate's dBase files. In September 1987, Borland purchased Ansa Software, including their Paradox/DOS 2.0 software. Notable classic versions were 3.5 and 4.5. Versions up to 3.5 were evolutions from 1.0. Version 4.0 and 4.5 were retooled in the Borland C++ windowing toolkit and used a different extended memory access scheme. Paradox/DOS was a successful DOS-based database of the late 1980s and early 1990s. At that time, dBase and its xBase clones (Foxpro, Clipper) dominated the market. Other notable competitors were Clarion, DataEase, R:Base, and DataFlex. The features that distinguished Paradox/DOS were: An enhanced design and implementation of visual Query by Example that was supported by an AI engine for heuristic, dynamic query optimization. Effective use of conventional, extended, and expanded memory – caching data tables and particularly indexes, which caused Paradox to execute tasks very quickly in contrast to the explicit skills required for xBase performance optimisation. An innovative programming language, the Paradox Application Language (PAL), that was readable, powerful, and could be recorded from keyboard actions (rather like Lotus 1-2-3 macro recording). Lotus-like text menus and windows, which was the native interface (in contrast to dBase, which had a command-line interface with menus layered on top). Particularly in Paradox 1.0 and 2.0, the user and programming manuals won readability awards – they were copiously illustrated, well laid out, and explanations were written in common English. There are a few MSDOS emulators, among which are https://dbdos.com/ (a paid-for product) and https://www.vdos.info/ (which has a freeware option), both of which provide the ability to run Paradox for DOS applications