Arrays'

There are two types of arrays in Solidity: fixed _arrays and dynamic _arrays:

// Array with a fixed length of 2 elements:

uint[2] fixedArray;

// another fixed Array, can contain 5 strings:

string[5] stringArray;

// a dynamic Array - has no fixed size, can keep growing:

uint[] dynamicArray;

You can also create an array of structs. Using the previous chapter's Person struct:

Person[] people; // dynamic Array, we can keep adding to it

Remember that state variables are stored permanently in the blockchain? So creating a dynamic array of structs like this can be useful for storing structured data in your contract, kind of like a database.

Public Arrays

You can declare an array as public, and Solidity will automatically create a getter method for it. The syntax looks like:

Person[] public people;

Other contracts would then be able to read (but not write) to this array. So this is a useful pattern for storing public data in your contract.