In a nutshell, a package is a set number of sessions and/or classes that are purchased in bulk.
Packages are mainly used to allow clients to purchase multiple sessions/classes at once. You can also use packages as a way to provide a discounted rate to clients who purchase more sessions/classes.
Here's a quick video on how to set this up:
Adding a new Package
To add a new package, click the '+' icon:
Fill in the details for the package:
Note: you can have any mixture of sessions or classes. For example you could have 10 sessions & 0 classes, or 10 classes & 0 sessions, or 10 sessions & 10 classes.