They Store items of the same data type at contiguous memory locations.

• They cannot be modified after its initialization; its size cannot be increased or decreased.

• Arrays are the simplest data structures.

• Syntax: dataType[] arrayName = new dataType[size];

  

Types of Arrays

1. Static Arrays:
   • Cannot be modified after initialization.
   • Size is fixed.
   • Example : Java, C++
2. Dynamic Arrays:
   • Can shrink and grow automatically.
   • Used in Python and JavaScript.
   • Example : Python, JavaScript
   • In Java, for dynamic arrays, we use "ArrayList."

Runtime Complexities

• Lookup by Index: O(1)
• Lookup by Value: O(n)
• Insert: O(n)
• Delete: O(n)