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Beginner 1 minute
What Is System Design?
System design is the practice of deciding how software pieces fit together before, and while, you build them. You sketch users, services, data stores, and the paths between them. The goal is not one perfect diagram. It is a design that meets product needs, stays understandable, and keeps working as traffic, data, and failures grow.
Key idea
Start with the user request, then follow it through compute, data, and response. Every arrow is a possible delay or failure.
See it in one picture
Follow the arrowsUsers
API
Data
Response
Follow the request
Real-world example
For a food delivery app, design covers mobile requests, restaurant search, order storage, payment, driver updates, and what happens when one service is temporarily unavailable.
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