Big O
Auto-discovered
Visit resource ↗Description
Big O is an interactive article on samwho.dev that teaches big O notation by measuring and visualizing how JavaScript examples slow down as input size grows.
It covers wall-clock timing versus asymptotic growth, constant, logarithmic, linear, and quadratic classes through sum loops, a closed-form sum, bubble sort, and binary search, then practical fixes such as Set lookups, avoiding indexOf inside loops, and caching factorial results.
It is for beginners and early-career programmers building intuition before formal complexity courses. Basic ability to read short JavaScript snippets is enough; no graphics background is required.
The page is a free long-form post with in-browser timers, steppers, and graphs. A short sponsor note appears near the top.
It is useful as a hands-on intro to why algorithm choice matters as inputs grow, before applying the same thinking to engine code hotspots.