Cryptocurrency exchanges are online platforms that support users exchange one cryptocurrency for another cryptocurrency, or for fiduciary currencies.
“Traditional” Cryptocurrency Exchanges
This type of exchange is similar to traditional stock exchanges, where buyers and sellers trade base on the current crypto market price through exchange’s assistance. Obviously, fees will be charged for each transaction. Some exchanges just allow users to deal only with cryptocurrencies, others allow users to trade fiduciary currencies for cryptocurrencies.
Examples for “Traditional” Cryptocurrency Exchanges: GDAX, Kraken, Binance, etc.
Direct Trading Platforms
These platforms offer direct peer-to-peer trading between buyers and sellers. Sellers set their own exchange rate and buyers can choose the best price in the market. This is the only solution in some regions where trading is limited to direct trading.
Examples for Direct Trading Platforms: Remitano (Vietnam only), etc.
Cryptocurrency Brokers
These are website-based exchanges which similar to those currency exchanges at an airport. They allow customers to buy and sell cryptocurrencies at a price set by the broker.
Examples for Cryptocurrency Brokers: Coinbase, Shapeshift, etc.
Cryptocurrency Funds
Funds are groups of professional traders that manage cryptocurrency assets. They allow public buy and hold cryptocurrency via the fund.
Examples for Cryptocurrency Funds: GBTC, etc.
List of top 15 exchanges (March 1st, 2018): (Source: cryptocoincharts)
1 Bitfinex (Marketshare: 28%)
2 Coinbase GDAX (Marketshare: 11%)
3 Coinone (Marketshare: 9%)
4 Kraken (Marketshare: 9%)
5 Bitstamp (Marketshare: 7%)
6 Bithumb (Marketshare: 5%)
7 Bitrrex (Marketshare: 5%)
8 HitBTC(Marketshare: 5%)
9 BTC-e/WEX (Marketshare: 3%)
10 Gemini (Marketshare: 3%)
11 BitFlyer (Marketshare: 3%)
12 Poloniex (Marketshare: 2%)
13 Quoine (Marketshare: 2%)
14 Binance (Marketshare: 1%)
15 EXMO (Marketshare: 1%)