Dai is a cryptocurrency established in 2014. Its value is USD 1.01. You can usually use the price to trade in a fixed and stock exchange, and most exchanges accept the dai currency. In transactions, according to my experience, it is not very fast, but not very slow. I think the transaction fee is normal, but if you are going to invest, I do not recommend it because the value is always stable, I do not recommend you to invest, the logo is stylish like bitcoin. But I think it's faster than most cryptocurrencies because the etherium-based fee is not too high I think it's a good cryptocurrency