In 1981, IBM commissioned a port of dBase for the then-in-development PC. The resultant program was one of the initial pieces of software available when the IBM PC went on sale the fall of 1981. dBase was one of a very few "professional" programs on the platform at that time, and became a huge success. The customer base included not only end-users, but an increasing number of "value added resellers", or VARs, who purchased dBase, wrote applications with it, and sold the completed systems to their customers. The May 1983 release of dBase II RunTime further entrenched dBase in the VAR market by allowing the VARs to deploy their products using the lower-cost RunTime system.