Linear structures
Arrays give O(1) index access. Stacks are LIFO and power recursion/undo systems. Queues are FIFO and model waiting lines and breadth-first search.
Linked lists shine at insert/delete in the middle when you already have a pointer, but random access is slower than arrays.
Trees and hash maps
Binary trees organize hierarchical data; binary search trees keep ordered lookup efficient when balanced. Hash maps offer average O(1) insert and lookup using keys.
For quizzes, memorize time complexities and one classic use case for each structure.