"Members" or "Users" refer to the individuals added to your RandomCoffee platform.
Each member has a unique identifier: his/her email address.
Each member may also have profile information (Country, Department, etc.), called "categories".
However, categories are optional. They allow you to unlock more advanced matchmaking rules, but you can perfectly enjoy the full RandomCoffee experience without adding any.
By default, all added members become "Active" in the Members list. In a very particular case (when you invite a member from the "Invite Link" section, by entering his email address), the user has a "Pending" status until he accepts the invitation and become "Active".