Optimized Systems Software

Optimized Systems Software (OSS) was a company that produced disk operating systems, programming languages with integrated development environments, and applications primarily for the Atari 8-bit family of home computers. OSS was best known for their enhanced versions of Atari DOS (OS A+, then DOS XL), Atari BASIC (first BASIC A+, then BASIC XL, and BASIC XE), and the Atari Assembler Editor (EASMD, then MAC/65), all of which were substantially improved over Atari's products, as well as the Action! programming language. OSS also sold some software for the Apple II.

OSS transitioned to 16-bit platforms with Personal Pascal for the Atari ST and Personal Prolog for Macintosh (which was also advertised for the Atari ST, but may not have been released). OSS was not as significant in those markets.