Delta tao Software is a small software company, located in, Citrus Heights, North California. It was founded in early 90s by Joe Williams and Tim Cotter. It develops and games and other software, mostly for Macintosh. Much of their work was in the 1990's, with games such as Clan Lord, Spaceward Ho, and Color Dark Castle.
- Erik's Ultimate Solitaire - A Famous software solitaire game.
- Spaceward Ho - Sci-Fi RTS game.
- Clan Lord - One of the first Mac MMORPGs.
- Color Dark Castle - Colorized version of Dark Castle.
- Strategic Conquest - Old mac RTS.
- Color MacCheese - Colorized classic mac game, "Mac Cheese"
- Return To Dark Castle - Long awaited sequel in the Dark Castle series of games, being developed by Z Sculpt. It originally was going to be produced by Delta Tao but was produced by the Cell phone Software company SuperHappyFunFun. It was released in March, 2008.