Learn the basics of java collections, including dynamic data structures, the list interface, and concrete classes like ArrayList. Compare non-generic and generic versions and explore add and get methods.

See how generics eliminate the need for typecasting and reduce compile-time and runtime errors when accessing data in lists, using student and teacher examples to illustrate safer, type-specific access.

Explore the Java collections framework hierarchy, focusing on List, Set, and Map interfaces and their insertion order rules. Learn how LinkedHashSet and LinkedHashMap preserve insertion order in common implementations.

Learn how to iterate an ArrayList of strings using for-each, an iterator, and a basic for loop, with examples like red, blue, green, and yellow.

LinkedHashSet preserves insertion order, unlike HashSet, which uses a hash table and linked list and does not guarantee order. Both avoid duplicates, letting you compare their behavior with sample code.

Explore how hash map implements the map interface to store key–value pairs with unique keys and no insertion order, using a hash table. See how put inserts and returns values.

Learn to iterate a hash map in Java with for-each, iterator, and lambda, printing keys and values from entries, keySet, and values.