| Structure | Key Property | Use Case Phrase |
|---|---|---|
| Array / List | O(1) access by index | "Use an array when you need fast indexed access." |
| Hash Map / Dict | O(1) average lookup by key | "I used a hash map to cache results and avoid recomputation." |
| Stack | LIFO — Last In, First Out | "A stack is ideal for tracking nested function calls." |
| Queue | FIFO — First In, First Out | "We use a queue to process jobs in order." |
| Tree | Hierarchical structure | "A binary search tree gives O(log n) lookups." |
| Graph | Nodes connected by edges | "We model the social network as a directed graph." |