Arrays are a simple data structure for storing lots of similar items. They exist in all programming languages, and are used as the basis for most other data structures. On their own, Arrays can be used to solve many interesting problems. Arrays come up very often in interview problems, and so being a guru with them is a must!

An Array is a collection of items. The items could be integers, strings, DVDs, games, books—anything really. The items are stored in neighboring (contiguous) memory locations. Because they're stored together, checking through the entire collection of items is straightforward.

Reference: https://leetcode.com/explore/learn/card/fun-with-arrays/521/introduction/3236/