Pragmaskeyword that enables certain compiler feature or checkscompiler version (pragma solidity ^0.8.0;)ABI Version (pragma abicoder v2;)experimental versions (pragma experimental smtchecker;)variables n suchcan be accessed by all functions of the contract and whose values are permanently stored on the blockchain. vs global vars like block timestamp, etc. Visibility:public - part of contract interface and can be either accessed internally or via messages/callsinternal - accessed internally fr...