A Library is a group of programs and program templates. This is where you can save programs and program templates to use for future learners.
A program is an intervention plan/protocol used to address a learner's hierarchical goals and/or behaviors consisting of 1) a user interface that includes instructions and instruments used to measure the application of the intervention and 2) a set of rules governing the automated assignment of goals and specifying their transition across phases and completion.
A program template is the structural pieces of a Motivity program (e.g. sets, target configuration, instruments, and mastery rules) that can be used to create new programs that use the same outline and configurations.
It's best practice is to create programs in a library and then assign them to the learner once the program is created. This way you have a copy of the program in the library where it can be easily found.