TCC gives you instant access to more than 265 internal commands. (By contrast, Microsoft's CMD has about 40 internal commands.) The best way to learn about commands is to experiment with them. This section will help you find the one(s) that you need, categorized in the lists below by name and by category.
Note: Remember that you can replace any internal command with an ALIAS or LIBRARY command or plugin. You can disable an internal command with COMMANDS or OPTION / Commands.