Hash Table
Domain: Programming Fundamentals
🎯 Motivation
Dictionaries use a hash table internally - it converts keys to numbers (hashes) for lightning-fast lookups.
📋 Concrete Example
When you do d['name'], Python hashes name to a number, jumps to that slot, and finds the value. O(1) - constant time, no matter how big the dict.
🔗 Analogy
A coat check at a event - you give your coat, they put it on a numbered hanger (hash). When you return with your ticket (key), they go straight to that number. Very fast.