What is a bit in computing?

Excuse me, but could you please elaborate on what exactly a "bit" refers to in the context of computing? I've heard it mentioned frequently, but I'm not entirely clear on its specific meaning and significance within the field. Is it a fundamental unit of measurement, perhaps akin to a byte or kilobyte? Or does it play a more nuanced role in how computers process and store information? I'd greatly appreciate any clarification you can provide.