Coaches and Users are separate items but some coaches could still be users. Here are the definitions of what they are on Home Campus.
Users: Anyone that has a login account on Home Campus who can make some sort of adjustments schedules, etc. Each school can have as many or as few coaches as they would like. It's completely up to you and how you want to delegate responsibilities. To learn more about Users Click Here.
Coaches: You can keep track of your coaches and their information (contact information, certifications, etc.). You will also want to make sure that you attach them to their sport so they will appear on the CIF directory. Click Here to learn how to do that.