It's digitalised art and assets. Do you still remember guys collecting post stamps or baseball cards. The rare and old ones costs a lot, but how can you transfer them or check the origin?
Well blockchain made it easy. It started with Crypto Punks which now costs a fortune:
Centralized exchange like crypto.com and binance want there cut from NFT market so they launched their own NFT market.
Wanna become NFT rockstar collector. Start with the baby steps. For the beggining you can just buy binance mystery box (which is collection of smaller nfts wrapped into the box) and sell nft 30 BUSD - 30 BNB each: