WTF is an SPV and Why Satoshi put it in the Bitcoin Whitepaper?

WTF is an SPV and Why Satoshi put it in the Bitcoin Whitepaper?

Simple Payment Verification, usually abbreviated to SPV, is a system outlined in the original Bitcoin Whitepaper that enables light clients (wallets running on low-end systems) to verify that a transaction has been included in Bitcoin and therefore a payment has been made.