ACTerm is a color terminal emulator that provides access to the core Unix functions of MAC OS X. Each terminal window is defined by a ACTerm session file or ACTSH file. The default startup is an interactive shell: bash (Bourne-again shell). ACTSH files can be launched from the desktop or through Finder. When ACTSH files are selected with finder they are loaded and the startup command is executed. Once the ACTerm application is running, new sessions may be created with Save-As or Save-To menu options, and existing ACTSH files can be opened without running to allow for updating startup commands and exit conditions. Each ACTSH file contains a color setup, initial position and size, along with a startup command. For advanced features like running scripts, new file extensions, or terminal application programming, a knowledge of shell programing is required. A working knowledge of the vi text editor is strongly recommended for all shell users.