This morning, I received a desperate letter from a person to remain nameless. "Quick!" it said, "Tell me a keyboard shortcut to mark IN on the timeline in QT Pro from where the playhead is parked. Having to twiddle those stupid triangles is frustrating beyond measure." Well, secret correspondent who shall be henceforth known as "V", here is a quick reference for you. I threw this together in short order, so if anyone has additional playback shortcuts they want to throw into the mix, please do so. If you've got a long commute, why not download Apple's QuickTime 7 Guide (pdf) and go straight to the source?

Space bar. Pause/play.

Right-Arrow. Move one frame forward in time.

Left-Arrow. Move one frame back in time.

Up-Arrow. Increase volume.

Down-Arrow. Decrease volume.

Command-A. Select the entire track.

Command-B. Select nothing. This has the very useful side effect of moving the selection triangles to the current location of the playhead.

Shift-Left Arrow. Move the left selection triangle to the playhead.

Shift-Right Arrow. Move the right selection triangle to the playhead.

Command-Left Arrow. Play in reverse.

Command-Right Arrow. Play.

Option-Left Arrow. Move left to the next selection triangle, or if there is none to the start of the movie.

Option-Right Arrow. Move right to the next selection triangle, or if there is none to the end of the movie.

Command-T. Play selection only.

Command-L. Loop playback.