System design is the process of defining the architecture, components, and interactions of a software system to meet requirements — especially for scalability, reliability, and performance. It's about how the pieces fit together to build systems that work at scale.
What system design covers
System design = the high-level structure of a system:
→ COMPONENTS → services, databases, caches, queues, load balancers, etc.
→ how they INTERACT → data flow, communication, APIs
→ meeting REQUIREMENTS → functional (what it does) + non-functional (scale, speed,
reliability, availability)
→ about the BIG PICTURE / architecture, not individual code
