Bancor network is a cross-chain DEX that ensures the liquidity of the tokens traded on it. It has created a big hype in its first beginning and now seems to be vanishing day by day. It was hacked for once several years ago causing a big loss of cryptocurrencies and everything becomes so bad since then. The community started raising a lot of questions about the necessity of BNT token and the progress of the exchange but nothing is really clear right now. As it is trusted and invested by a lot of people, I really hope they improve their product soon (and explain more about the token).