I've used Redis in production for almost a decade. It's reliable and easy to use (if used correctly). Here are my top 5 use cases where it shines:

The most common use case is to utilize Redis for caching. This helps protect the database layer from overloading. Redis offers fast lookup for cached data and can help improve application performance.

We use Redis to share user session data among stateless servers. Redis provides a centralized place to store session data and makes it easy to scale out servers.

We use Redis distributed locks to grant mutually exclusive access to shared resources. This prevents race conditions in distributed systems. Redis locks are easy to implement and automatically expire.

We use Redis to track like counts, view counts etc on social media apps. Redis counters provide atomic increments/decrements. We also use Redis to enforce rate limits on our API endpoints. This helps prevent abuse.

Sorted sets make it easy to implement gaming leaderboards in Redis. We can add, update, or remove users from the leaderboard and query ranges efficiently.

There are many other features in Redis. What are some other real-world use cases where you've used Redis successfully?