Inheritance
Inheritance is one of the pillars of object orientation and Solidity supports inheritance between smart contracts. Inheritance is the process of defining multiple contracts that are related to each other through parent-child relationships. The contract that is inherited is called the parent contract and the contract that inherits is called the child contract. Similarly, the contract has a parent known as the derived class and the parent contract is known as a base contract. Inheritance is mostly about code-reusability. There is a is-a relationship between base and derived contracts and all public and internal scoped functions and state variables are available to derived contracts. In fact, Solidity compiler copies the base contract bytecode into derived contract bytecode. The is keyword is used to inherit the base contract in the derived contract.
It is one of the most important concepts that should be mastered by every Solidity developer because of the way contracts are versioned...
