Does Gmail use data or wifi?

Excuse me, could you clarify something for me? I've been wondering, when it comes to Gmail, does it rely solely on data to function, or can it also utilize wifi networks for connectivity? I'm curious about the technical aspect of how Gmail accesses the internet to send and receive emails. I understand that data and wifi are both means of connecting to the internet, but I'm not sure which one Gmail prefers or if it's capable of using both interchangeably. Could you enlighten me on this matter?