Proof of Work (PoW) as the name states is the approval of the work that happened and demonstrating it is right.
Bitcoin and numerous alternative coins use PoW in order to ensure the credibility of the chain. The Proof of work idea existed even before Bitcoin, however, Satoshi Nakamoto connected this strategy to Bitcoin, thereby altering the way conventional transactions are conducted.
Math exam
To see how it functions in straightforward terms, accept that you are in a math exam alongside different students in a classroom. The student who can think of the right answer as well as can concoct the total evidence of the process of finding that right answer gets the reward. As we probably are aware this needs the student with a considerable measure of intellectual competence which normally expends a great deal of effort.
Going further, confirmation of work is a prerequisite to characterize a costly PC figuring. This process also called "mining", should be performed with a focus on the end goal of making another gathering of trustless transactions which is publically recorded on an electronic ledger, called the "blockchain".
The process of mining fills several needs
1- To confirm the authenticity of a transfer while preventing double-spending; and,
2- To record that transaction, while broadcasting the update in the blockchain to all nodes; thereby solidifying the security of the system.
PoW
Transactions are packaged together into what we call a block. Miners check the accuracy of the transactions inside each block to prevent double spending and fraud. To do this, miners must perform the aforementioned mathematical equation, thereby showing "proof-of-work". A reward is given to the miner who solves each portion of that equation first; and, verified transactions are completed and recorded in the general blockchain, thereby installing that block into the blockchain, ensuring its security through that official recordation.
As each idea or approach may have its own advantages and drawbacks, likewise PoW has its own drawbacks. Firstly, PoW requires more electric power which costs the miners a portion of any potential profits they may make for their participation. The hardware needed the for high-speed computations involved in the mining process is also prohibitive to many potential miners. For these reasons the PoW network employed by Bitcoin, there is the possibility of miners abandoning their efforts toward building the Bitcoin blockchain and reconfiguring their equipment to mine an alternate coin if the reward is more lucrative.
The conundrum is that while the work must be respectably hard on the mining side, it must be simple to check for the system in order for future blocks to be mined. This delicate balance is known as CPU evaluating capacity.
While the system is not perfect; it is fully functional and secure. The mining process that drives the Bitcoin blockchain, and the coin itself, demands Proof-of-Work for verification and safe transfer of funds; which provides the world with a much-needed payment platform that cannot be disputed.