Memberships and Attributes/Interests/Etc.

We are looking into memberships and whether they have to be linked to donations/financial support/contributions/etc. Do memberships need to be linked to contributions or can we link them to attributes/interests/etc…? I know the main purpose of memberships is for tracking giving but I wasn't sure if anyone had used it for other purposes. If anyone has any information on the subject or other insights into the matter, please let me know. I’m fairly new to the software so I appreciate an open forum for these kinds of inquiries. Thank you all very much!