.CS File Extension

Source code file used by Microsoft Visual C# (C Sharp) and C# .NET development software, which is included in Microsoft Visual Studio; often used for developing software components that are implemented distributed environments; can be opened by Microsoft development software or other C# programming applications.

File created by ColorSchemer Studio, a program used for developing color palettes for websites, magazines, home decoration, and other target mediums; saves the user's color schemes, which often contain complementary colors that are matched with one another on the color spectrum.

Custom script written for CLEO 3, a third-party scripting engine for Grand Theft Auto: San Andreas (GTA SA); allows players to expand the capabilities of the game using custom functions called "opcodes;" may be created with Sanny Builder, a GTA mod utility.

In order to use a CS file with GTA SA, it must be stored in the "game\CLEO" folder.