TID is a system file associated with software developed by TruKnox Technologies. TID file store information about network traffic generated by given application as it runs.

The presence of a TID files means that one or more of the following tools are installed on the computer: Tru-Designer, Tru-Sheluder, or Tru-Player. Each of the tools has a different purpose, but all are paid software available for Microsoft Windows systems.