Split selected region or event at the playhead

`Command` + `T`

All hotkeys for Garageband 10 (MacOS)

Track Operations Create a new track	`Option` + `Command` + `N`
Track Operations Create a new audio track	`Option` + `Command` + `A`
Track Operations Create a new software instrument track	`Option` + `Command` + `S`
Track Operations Duplicate the selected track	`Command` + `D`
Track Operations Delete the selected track	`Command` + `Delete`
Track Operations Rename the selected track	`Shift` + `Return`
Track Operations Select the next higher track	`Up Arrow`
Track Operations Select the next lower track	`Down Arrow`
Track Operations Mute/Unmute the selected track	`M`
Track Operations Solo/Unsolo the selected track	`S`
Track Operations Turn monitoring for the selected track on/off	`Ctrl` + `I`
Track Operations Show/Hide automation for the selected track	`A`
Track Operations Delete all automation on the selected track	`Ctrl` + `Shift` + `Command` + `Delete`
Track Operations Unmute all tracks	`Ctrl` + `Option + Command + M`
Track Operations Unsolo all tracks	`Ctrl` + `Option + Command + S`
Edit Track Undo	`Command` + `Z`
Edit Track Redo	`Shift` + `Command` + `Z`
Edit Track Cut	`Command` + `X`
Edit Track Cut an arrangement marker together with its regions	`Option` + `Command` + `Delete`
Edit Track Copy	`Command` + `C`
Edit Track Paste	`Command` + `V`
Edit Track Delete	`Delete`
MIsellaneous Shortcuts Select all	`Command` + `A`
MIsellaneous Shortcuts Select previous region on the selected track	`Left Arrow`
MIsellaneous Shortcuts Select next region on the selected track	`Right Arrow`
MIsellaneous Shortcuts Split selected region or event at the playhead	`Command` + `T`
MIsellaneous Shortcuts Join selected regions or notes	`Command` + `J`
MIsellaneous Shortcuts Loop selected region continuously	`L`
MIsellaneous Shortcuts Add selected region to the Apple Loops Library	`Ctrl` + `Shift` + `O`
MIsellaneous Shortcuts Rename the selected region	`Shift` + `N`
MIsellaneous Shortcuts Turn Snap to Grid on/off	`Command` + `G`
MIsellaneous Shortcuts Show/Hide alignment guides	`Option` + `Command` + `G`
MIsellaneous Shortcuts Start recording	`R`
MIsellaneous Shortcuts Turn the Record Enable button for the selected track on/off	`Ctrl` + `R`
MIsellaneous Shortcuts Turn the cycle area on/off	`C`
MIsellaneous Shortcuts Turn the metronome on/off	`K`
MIsellaneous Shortcuts Turn count+in on/off	`Shift` + `K`
MIsellaneous Shortcuts Transpose selected notes up one semitone	`Option` + `Up Arrow`
MIsellaneous Shortcuts Transpose selected notes down one semitone	`Option` + `Down Arrow`
MIsellaneous Shortcuts Transpose selected notes up one octave	`Option` + `Shift` + `Up Arrow`
MIsellaneous Shortcuts Transpose selected notes down one octave	`Option` + `Shift` + `Down Arrow`
MIsellaneous Shortcuts Select the next score event	`Right Arrow`
MIsellaneous Shortcuts Select the previous score event	`Left Arrow`
MIsellaneous Shortcuts Select the next staff event	`Down Arrow`
MIsellaneous Shortcuts Select the previous staff event	`Up Arrow`
MIsellaneous Shortcuts Print score notation	`Command` + `P`
Display Objects Show/Hide the Musical Typing window	`Command` + `K`
Display Objects Show/Hide Smart Controls	`B`
Display Objects Show/Hide the Score Editor	`N`
Display Objects Show/Hide the Piano Roll Editor	`P`
Display Objects Show/Hide the Loop Browser	`O`
Display Objects Show/Hide the Library	`Y`
Display Objects Show/Hide the Editor	`E`
Display Objects Show/Hide the NotePad	`Option` + `Command` + `P`
Display Objects Show/Hide the Media Browser	`F`
Display Objects Show/Hide the Arrangement track	`Shift` + `Command` + `A`
Display Objects Show/Hide the Movie track	`Shift` + `Command` + `O`
Display Objects Show/Hide theTransposition track	`Shift` + `Command` + `X`
Display Objects Show/Hide the Tempo track	`Shift` + `Command` + `T`
Display Objects Show/Hide the Master track	`Shift` + `Command` + `M`
General Shortcuts Open a Movie	`Option` + `Command` + `O`
General Shortcuts Create a new project	`Command` + `N`
General Shortcuts Open an existing project	`Command` + `O`
General Shortcuts Close the current window or project	`Command` + `W`
General Shortcuts Minimize the GarageBand window	`Command` + `M`
General Shortcuts Save the current project	`Command` + `S`
General Shortcuts Save As	`Shift` + `Command` + `S`
General Shortcuts Show GarageBand preferences	`Command` + `,`
General Shortcuts Hide GarageBand	`Command` + `H`
General Shortcuts Quit GarageBand	`Command` + `Q`
General Shortcuts Open detailed Help (move the pointer over an interface item)	`Command` + `?`
General Shortcuts Start or stop playback	`Spacebar`
General Shortcuts Go to beginning	`Return`
General Shortcuts Go to end of last region	`Option` + `Return`
General Shortcuts Move forward	`.`
General Shortcuts Move back	`,`
General Shortcuts Move cycle area forward	`Shift` + `Command` + `.`
General Shortcuts Move cycle area back	`Shift` + `Command` + `,`
General Shortcuts Move forward by visible width of the timeline	`End`
General Shortcuts Move back by visible width of the timeline	`Home`
General Shortcuts Turn Catch mode on/off	`<`
General Shortcuts Zoom out	`Command` + `Left Arrow`
General Shortcuts Zoom in	`Command` + `Right Arrow`