Mining pools

Due to the huge mining hash rate, people from the mining community came together to mine blocks together and decided to split the reward depending on how much hash power each was contributing to the pool. In a mining pool, everyone gets a share of the block reward directly proportional to the resources invested. Many mining pools exist nowadays. Some of the popular mining pools are these:

• BTC.com: This is one of the largest mining pools, responsible for around 25% of Bitcoin blocks mined on a regular basis as of June, 2018. The pool was launched in September, 2016, and is currently owned by Bitmain Technologies Ltd.
• Antpool: This is owned by the same company that owns Btc.com, one of the largest mining pools. Antpool and Btc.com share the top positions among the largest mining pools. Bitmain is based in Beijing, China.
• ViaBTC: This was founded in May, 2016, and is owned by Viabtc Technology. It is based in China. 
• SlushPool: This is the world's first mining pool. It started on November 27, 2010, and went by the name of Bitcoin Pooled Mining Server. The pool has mined over 1 million BTC since its launch. It is a reliable and stable pool with a history of accurate payouts.

The following diagram shows the percentage of Bitcoins mined by the various Bitcoin mining pools between June 1 and June 2, 2018:

Apart from the ones we have mentioned, there are many mining pools that actively mine and keep on adding more and more features in the race to become the largest mining pool.