Data structures form the foundation for efficient algorithms and smart system design. They are a must to know. Linked List Useful when you need to insert or delete items frequently, especially in the middle of the list, without shifting elements like you would in an array. Array One of the simplest DS. Great for storing ordered lists where you need fast access or modification by position. Hashmap Perfect when you need quick access to data using a unique key, like looking up information in databa

Difference between HashMap and Hashtable