Binary Search
Domain: Algorithms
🎯 Motivation
On sorted data, repeatedly halve the search range: check the middle, discard the half that cannot contain the target. O(log n).
📋 Concrete Example
Search for 25 in sorted [10, 20, 25, 30, 40, 50]: middle is 30, 25 < 30 so search left half. Middle of [10, 20, 25] is 20, 25 > 20 so search right. Found 25!
🔗 Analogy
Guessing a number between 1 and 100. You always guess the middle (50). If told higher, you guess 75. Each guess eliminates half the remaining numbers.