File created by Finale, a music notation application; contains sequencer track/channel-to-Finale staff configuration data that is referenced when opening a .MID file in Finale; the configuration data helps translate the tracks from the MID file into Finale.

To create a TRK file, open your desired MID file by selecting File → Open... and double-clicking the MID file, click Set Track-to-Staff List, customize your track/staff configuration, and click Save. To open a TRK file, first open your MID file by selecting File → Open..., select "Standard MIDI File" in the drop down menu, double-click your MID file, click Track-to-Staff List, click Load, and double-click the TRK file you want to open.

File created by Garmin GPS devices, including the PCX5, PCX5AVD, and PC150 models; contains a series of locations, or route points, that are logged in real-time while a user navigates with a GPS unit; includes software version, coordinate system, latitude, longitude, date, and altitude.

TRK files are used to record traveling logs. They are stored in an ASCII text format.

File created by Pacific Fighters, a flight simulator game; contains a recording of a flight mission in "offline" mode; created by clicking the Save Track button when a mission is complete; can be played back in Pacific Fighter.

Tracks recorded in "online" mode are stored in .NTRK files. Unlike NTRK files, TRK files only store initial positions and player inputs rather than all object positions during a mission. NOTE: TRK files do not contain video data. They only store the initial positions and the player control inputs.