Functions can be declared as

| Visibility | Description | | ---------- | ------------------------------------------------------------------ | | public | Any contract and account can call | | private | Accessible only inside the contract that defines the function | | internal | Accessible only inside contract that inherits an internal function | | external | Accessible only other contracts and accounts can call |

State variables can be declared as public, private, or internal but not external.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.15;

contract ViewAndPure {
    uint public gamePoints = 0;


    // No modification or reading from the state
    function checkRewards(uint multiplier, uint points) public pure returns (uint) {
        return multiplier * points;
    }

    // No modification but can read from the state
    function addGamePoints(uint newScore) public view returns (uint) {
        return gamePoints + newScore;
    }

}

If you call view or pure functions externally, you do not pay a gas fee.

Read more about storage and memory here