Not every network calls them members. You might have subscribers, partners, franchisees, affiliates or clients. Under Naming in Membership Settings, set the Singular and Plural you use.
What changes
Headings across the app and in the customer portal. The left-hand menu item and the screen titles pick up your word, so your team stops translating between the product's vocabulary and yours.
What does not
NOTHING IS RENAMED IN YOUR DATA OR YOUR EXPORTS
Leave it blank for the default
An empty field falls back to Member and Memberships. You can change your mind whenever you like — it is a label, and nothing depends on it.