Introduction

Welcome to System Design!

Every large system starts with a simple question: how do we keep an application working when the number of users, requests, and amount of data grows by hundreds of times? That is exactly the kind of question System Design helps answer.

It is not enough to memorize a set of technologies or draw a few boxes with arrows. The important part is learning to identify requirements, find bottlenecks, compare alternatives, and understand why one architectural decision fits a system while another does not.

As you move through the course, you will:

• translate product requirements into technical constraints and goals;
• estimate traffic, data volume, and required throughput;
• understand when caching, queues, replication, sharding, and load balancing are needed;
• learn to choose between consistency, availability, speed, and solution complexity;
• combine individual components into a complete and resilient system.

How to get the most out of the course

The routine is simple: study an idea → try applying it to a system → compare several alternatives → return to the part where the decision is still unclear. In System Design, there is rarely a single correct answer. What matters much more is being able to explain your choice and its trade-offs.