Before we dive into designing complex distributed systems, we need to establish a solid foundation. These fundamental concepts are the building blocks that every system designer must understand.

Think of this section as learning the alphabet before writing essays. You wouldn’t try to design a scalable web application without understanding how the internet routes requests, right?

What You’ll Learn

In this section, we’ll cover the essential concepts that underpin all distributed systems:

  • Domain Name System (DNS): The internet’s phonebook that translates human-readable domain names into IP addresses
  • Client-Server Architecture: The fundamental model of how computers communicate
  • Network Protocols: HTTP, REST, and how modern APIs work
  • Data Partitioning and Sharding: Dividing data across multiple machines
  • Replication: Keeping multiple copies of data for reliability and performance
  • Consistency Models: Understanding trade-offs in distributed data

These aren’t just theoretical concepts—they’re the practical tools you’ll use in every system design interview and in building real-world systems.

Why These Matter

Every large-scale system you use daily—Google, Netflix, Amazon—relies on these fundamental concepts. Understanding them will help you:

  • Make informed architectural decisions
  • Communicate effectively with other engineers
  • Identify potential bottlenecks and failure points
  • Design systems that actually work at scale

Let’s build that foundation together!


Approximate Calculations for System Design Interviews

Complete guide to approximate calculations covering capacity estimation, bandwidth calculations, QPS estimation, storage planning, and latency numbers every engineer should know.

Failure Models in Distributed Systems

Complete guide to failure models covering crash failures, omission failures, Byzantine failures, network partitions, and fallacies of distributed systems.

Consistency Models in Distributed Systems

Complete guide to consistency models covering strong consistency, eventual consistency, CAP theorem, linearizability, and trade-offs in distributed systems.

Abstractions in System Design - Building Modular Systems

Understanding abstractions in system design covering abstraction layers, APIs, interfaces, and how they help manage complexity in distributed systems.

Domain Name System (DNS) Explained

Complete guide to understanding DNS (Domain Name System), how it works as the internet’s phonebook, DNS architecture, and resource record types for system design interviews.