Welcome to System Design Concepts

This course teaches you how to design scalable systems from scratch. You'll learn a structured process for approaching any design problem, how to estimate scale, and the core building blocks that every distributed system is made of.

What You'll Learn

• A repeatable framework for tackling system design problems
• Back-of-envelope estimation (QPS, storage, bandwidth)
• Networking fundamentals: TCP vs UDP, DNS, HTTP versions
• Infrastructure: proxies, load balancers, caches, CDNs
• Data layer: SQL vs NoSQL, replication, sharding, object storage, consistency models
• Communication patterns: REST, gRPC, WebSockets, message queues
• Reliability: idempotency, rate limiting, monitoring, failure handling

Why This Course?

System design interviews test whether you can reason about tradeoffs at scale. But these concepts also show up every day in real engineering work. Understanding them makes you a better builder, whether you're designing a new service or debugging a production outage.

Prerequisites

• Basic programming experience in any language
• Familiarity with HTTP and REST APIs
• Some exposure to databases (SQL basics)

Course Structure

The first two lessons teach you the process: how to approach a design and how to estimate scale. The remaining lessons cover one building block each, with real-world examples and tradeoff analysis. By the end, you'll be able to assemble these pieces into a complete system design.