Terminals are computer-like devices that can be found in the main game as well as custom levels. Typically, terminals have an activity zone that the player can activate by pressing the interact key to run the predetermined script.
Terminals can only be activated once, until the room is reloaded.
In Dimension VVVVVV, the main purpose of most terminals is to store research notes or lore, and may help the player navigate the dimension by revealing areas of interest. Some terminals in the main campaign are there for decorative purposes and cannot be interacted with (e.g. in Comms Relay).
One notable terminal is the Dimensional Stability Generator in the Final Level, which is the only terminal that is required to use to complete the game.
For a list of all terminals that appear in VVVVVV's campaign, see List of campaign terminals.