Bittrex is one of the larger crypto to crypto exchanges offering a large number of trading pairs into bitcoin.
The exchange does have a very high turnover crypto currencies - leading some to accuse it of allowing pump and dump schemes that erode confidence in the crypto currency ecosystem as a whole.
Every single transaction is traceable and irretrievably stored in the blockchain.
Your coins and deposits are available and tradable 24 hours a day, 7 days a week.
The registration is free, depending on the provider there are different fees for the trade.