What are collections, and can you explain them in detail with real-time use cases?

Question

Accepted Answer

Collections are data structures that store groups of related objects, enabling efficient data management and manipulation.

ArrayList: A resizable array implementation in Java, useful for storing lists of items like user profiles in a social media app.
HashMap: A key-value pair collection that allows for fast retrieval, ideal for caching user sessions in a web application.
HashSet: A collection that prevents duplicates, useful for maintaining a unique list of email addresses during user registration.
LinkedList: A collection that allows for efficient insertions and deletions, suitable for implementing a playlist in a music application.
TreeSet: A sorted collection that maintains order, useful for storing and retrieving sorted data like leaderboard scores.

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