A mining pool as its name suggests is a group of cooperating machines working together using their collective computing power to crack the current block difficulty. For the average user, this is the only option they really have to reap the rewards from cryptocurrency mining. The majority of mining pools are centralized in China due to the abundance of cheap electricity.
The next obvious question is what are the best pools to join? There are 20 major mining pools that you can choose from. Reffer to the pie chart below to see the distribution of computing power by mining pool.
All these websites offer very similar services the only things that differ from site to site is the cut or the fee that is applied to your payouts from the pool. Bitcoin miners can constantly switch pools easily if desired to maximize their profits. This means the market share of pools is constantly changing.