The world is so much interested about decentralized exchanges. This is why because, Centralized exchanges are at the hands of a central authority – or intermediary who oversees and controls your funds, personal details and transaction history. When trading and transacting on centralized exchanges, one should know that your funds aren’t sent P2P – or directly to another user – and must first pass through a centralized middleman, who authorizes and executes the trade on your behalf.
I wrote a detailed article on centralized vs decentralized exchanges here. https://cryptoexchange4u.com/2018/07/25/centralized-versus-decentralized-exchanges/
have a read.
Meanwhile, you can check out our cryptocurrency exchange script and avail the demo.