The proof of work technology is developed with the help of hashes which are essentially long strings of numbers. Once we apply a given set of data through a hash function, the blockchain will create only one hash. Even a tiny change to any portion of the original data will result in a totally unrecognizable hash. The hash generated by a given function has a single approach function and it cannot be used to reverse engineer and obtain the actual data. One can surely check this generated data to see if the hash is matching the original data, but he/she cannot alter or edit it in any way.
Generating a hash for a set of transactions would be difficult for the present computing power, so it is processed into work for miners and the network creates a certain level of difficulty setting which is achieved by creating a target for the hash. Once this target is achieved, the data is authenticated.
Mining: The authentication of transactions/ data/ blocks VIA solving algorithms is the basic function of mining. With every block addition, these algorithms increase in their level of difficulty thus requiring immense computing power to maintain their pace as well as efficiency. To ensure smooth functioning of the blockchain, the cryptocurrency entrepreneurs encourage association with numerous computer networks. As soon as there is a block addition on the blockchain, all the computers work on solving the algorithm. The computer that is first able to solve the algorithm accurately, authenticates the transaction and all the following networks have to verify the same, thus updating the blockchain. The computing ‘work’ is paid in the form of cryptocurrencies; this process is called ‘mining’ and the people who mine these cryptocurrencies are called ‘miners’.
To understand the proof of work principle completely, we also need to understand that anyone can create a block; hence, we must find a way to decide which block should be trusted. Users are guided to simply trust the longest valid chain with the highest amount of work to be the most authentic chain. Proof of work makes it extremely difficult to alter any aspect of the blockchain, since such an alteration would require re-mining of all the subsequent blocks, which is immensely expensive.