When to Use Arrays in Java?

Arrays are used to store multiple values in a single variable, instead of declaring separate variables for each value.

When should an array be used?

An array is a data structure, which can store a fixed-size collection of elements of the same data type. An array is used to store a collection of data, but it is often more useful to think of an array as a collection of variables of the same type.

When would you use array and when would you use ArrayList?

Since an array is static in nature i.e. you cannot change the size of an array once created, So, if you need an array which can resize itself then you should use the ArrayList. This is the fundamental difference between an array and an ArrayList.