Is BitMart a Blockchain?

Excuse me, but I couldn't help but notice the mention of BitMart in the conversation. I'm a bit confused about something - is BitMart actually a blockchain in itself? From my understanding, blockchain is the underlying technology that supports cryptocurrencies and decentralized systems, while BitMart seems to be a cryptocurrency exchange platform. Could you clarify if there's a misunderstanding here, or if BitMart somehow incorporates blockchain technology in a unique way? Thank you in advance for your explanation.