At this time it was available only for the DOS operating system. This software could be customized by using the MapCode development environment which was a C -like programming language. The name was subsequently changed to just "MapInfo" upon its second release. MapInfo was redesigned with an easier-to-use graphical user interface and was also made available for the UNIX and Macintosh operating systems. The MapCode development environment was replaced with a new language called MapBasic. Version 4 of the product, released in , saw the product renamed to "MapInfo Professional".