What is the difference between Binance and smart chain?

Could you elaborate on the key distinctions between Binance and Smart Chain? I've heard they're both related to cryptocurrency but seem to serve different purposes. For Binance, does it primarily function as an exchange platform for various cryptocurrencies? And when it comes to Smart Chain, does it operate more as a decentralized blockchain network, supporting smart contracts and decentralized applications? I'm curious to understand the fundamental differences in their architecture, functionality, and the use cases they cater to in the cryptocurrency ecosystem.