📚 Resources 11 — Go Deeper on Algorithms & Data Structures

All free unless marked otherwise. None are required — pick whatever matches how you like to learn.

🖱️ Interactive

VisuAlgo — beautiful, click-to-play animations of sorting, searching, trees, graphs, and more, built by a university team. Best for visual learners who want to watch the recipes from this module run step by step.
University of San Francisco — Data Structure Visualizations — a classic, plainer set of animations covering nearly every structure in this module. Best for slowly stepping through one operation at a time at your own pace.

CS50’s algorithms lecture — Harvard’s famous free intro course; the week on algorithms includes the legendary live phone-book demonstration. Best for people who enjoy an energetic lecture and don’t mind ~1 hour. (Find the “Algorithms” week on the course page — no sign-up needed to watch.)
Crash Course Computer Science — “Intro to Algorithms” and “Data Structures” — episodes 13 and 14 of a fast, friendly animated series. Best for a 12-minute refresher of this whole module.
AlgoRythmics — sorting algorithms as folk dances — a Hungarian university troupe performs bubble sort and merge sort as actual folk dances. Genuinely famous, genuinely delightful. Best for anyone who thinks they “don’t get” sorting — you will after watching people dance it.

Grokking Algorithms by Aditya Bhargava (paid book, optional) — widely considered the friendliest algorithms book ever written: hand-drawn pictures, everyday examples, minimal math. Best for readers who finished this module hungry for one gentle step further. Your local library may have it.