Interactive Course

Learn Redis by doing,
not by reading docs.

Redis is a database that lives in RAM instead of on disk — that makes it thousands of times faster than a regular database. These 4 lessons cover the patterns that power 90% of Redis usage in real apps.

📦
Lesson 1
Caching
Your database query takes 2 seconds. Redis answers the same question in under 1ms — by remembering the answer.
SET key value EX 30
🔢
Lesson 2
Atomic Counters
50,000 users click "Like" simultaneously. Redis handles every single one correctly — no race conditions, no lost counts.
INCR page:views
🚦
Lesson 3
Rate Limiting
A bot is hammering your API with 10,000 requests per minute. Redis counts and blocks — and automatically resets the window.
INCR + EXPIRE
🏆
Lesson 4
Leaderboards
1 million players, always ranked by score. Redis Sorted Sets stay sorted as you write — no ORDER BY at read time.
ZADD leaderboard 1500 "alice"
💡 How to use this app

Each lesson is interactive — you trigger real Redis commands and see exactly what happens. Visit the 🔑 Inspect tab at any time to see every key currently stored in your Redis instance, its type, and when it expires.

Try this order: start with Caching, refresh the page twice to see the speed difference, then work through the rest in order.