Array

Organize items sequentially.

• lookup O(1) - search item, for example array[0]

• append:

• • push O(1) - Add at the end of the array:

  • pop O(1) - Remove the last item of the array

• insert:

• • unshift O(n) - Insert at the start of the array

• delete:

• • splice O(n) - Insert or delete

There are two types of array:

1. Static array - the length of an array or the size is predetermined, like in Java

2. Dynamic array - the size of an array is not predetermined. If you need to add data, the array will be rebuilt at a new location with more memory. That is why the append can be O(n) because it need to loop all over again to rebuild the array