Code on this website refers to programming code or languages used to control computing devices or other programs. For example, PHP, Javascript, HTML, and CSS are common programming languages for building websites. For operating systems, the languages differ depending on the operating system, UNIX and Linux related systems use shell script lanaguages, like sh or perl, the C programming language, C++, objective C or assembly languages. SQL is a common database language. For spreadsheets, there are formulas and macros. Anything that can be automated or needs to communicate has a language.