
Logic Pro for Mac Library interface
You can view available patches for the currently selected track, and choose a new patch, in the Library. Categories appear on the left, and patches for the selected category are displayed on the right. You can search for patches, create, save, and delete patches, and choose routing options.
You can view all available patches for the track, or view only patches for a particular sound pack.
When a software instrument track with Session Player as the default region type is selected, you can choose some settings in the Library.

Track icon: The icon for the selected track is displayed in the upper part of the Library.
View pop-up menu: Choose which patches to display. You can display all available patches, or filter patches by sound pack.
Search field: Quickly search for patches by name.
Category and Patch lists: Select a category on the left, then select a patch on the right.
Options pop-up menu: Define the default patch and merge patches.
Revert button: Revert to the saved settings for a patch, erasing any changes you have made.
Delete button: Delete a saved patch.
Save button: Save the patch with its current settings as a new custom patch.
You can also access the following file types in the Library, when the corresponding item is selected:
Channel strip settings (.cst)
Plug-in presets (.pst)
Sampler instruments (.exs)
Environment instruments, and programs or banks of MIDI instruments created in the Audio MIDI Setup utility
Open the Library
Do one of the following:
Click the Library button
in the control bar.
Choose View > Show Library.
For information about using the Library, see Logic Pro for Mac patches overview.