Is MetaMask AVAX or AVAX?

Excuse me, I'm a bit confused about MetaMask and AVAX. I've heard these terms being used interchangeably, but I'm not quite sure if they're the same thing or different. Could you clarify for me? Is MetaMask synonymous with AVAX, or are they two separate entities with distinct functionalities? I'm trying to understand the nuances of this crypto world, and your explanation would be greatly appreciated.