Mining Wholesale is a privately owned company based in The Netherlands, which focuses on the exploitation of mining-related products to consumers and businesses.
MinerGate is a cryptocurrency mining brand. The platform provides convenient software for mining a number of crypto coins and a mining pool in which this software or one of the supported side apps can be used. The platform was founded in 2014 and has gained a multi-million user base since then.
Although NiceHash is usually regarded as a mining service, it's better to say that it's a kind of a platform for selling/buying cloud mining contracts. What is special about NiceHash is that users can opt for both selling and buying the hash power on this platform.
MoneroHash is a US mining pool created solely for Monero mining. Since 2014 it is run by a single person. The fee is 1.6 and a part of this amount is given to open source developers. The payouts occur every 24 hour (in case if the threshold is reached). There's an option to send the mined coins straight to the exchange wallet. It saves users some money that could be spent on transaction fees.