When looking up and selecting a contact file in the Sales module within the Sales Channel context, besides the name of the contact a series of little symbols can appear. This is what they stand for:
Membership: You'll be able to see a snapshot of which one just by sliding the mouse over the symbol.
The contact currently has a marketing offer, a.k.a. an advantage assigned to them. You can see these in the general tab of the information menu of the contact file, in the marketing alerts section.
Note: When one or more notes are created within a contact file, this symbol will be displayed next to the name when a contact search is made from the sales menus in the Sales Channel context.
Credit balance: This is the amount of money the contact has available to spend in your institution. For example: When an event is cancelled, contacts can be directly refunded on their credit cards,
Pending account allowed: This is the amount that your institution allows a contact to pay with some delay. For example: When a school buys tickets for its students to go to a museum, they don't usually pay on the spot. The pending account allows the school to pay after the visit of the students.