# Tab Functions
> [HTML Version](tab-functions.htm)
Tab 'functions', while conforming to standard function syntax, are not real functions in that they don't return any value. Instead, they perform some kind of terminal / file / client output or control operation. For this reason and because there are so many of them, especially in the sub-category of ATE Functions, they are covered in their own section of the documentation: [Tab Functions](tabfunctions.htm.md).