What Is a Simplified Payment Verification (SPV)?
A Simplified Payment Verification (SPV) is a method of verifying Bitcoin transactions without having to download the entire blockchain. It was first proposed by Satoshi Nakamoto in his original white paper on Bitcoin and has since become an integral part of the cryptocurrency ecosystem. SPV allows users to verify that their payments have been received, as well as check for double-spending, without downloading the full blockchain or trusting any third party.
The way it works is that instead of downloading all blocks from the network, SPV clients only need to download block headers which contain information about each transaction such as its hash and timestamp. This data can then be used to validate whether a particular transaction exists within the blockchain or not. Additionally, because this process requires less computing power than downloading every single block, it makes using Bitcoin much more efficient and cost effective for users who don’t want to store large amounts of data on their computers.