Core Concepts
10 topics in core concepts.
Scalability
Every production system eventually faces growth. If your architecture cannot scale, you will hit a wall — either the system crashes under load, or you.
Availability
Users and businesses depend on systems being available. A payment system that goes down for 1 hour can cost millions of dollars.
Reliability
A system can be available (running) but unreliable (returning wrong results). A payment system that double-charges customers is available but unreliable.
Single Point of Failure (SPOF)
Identifying and eliminating SPOFs is one of the first things an interviewer expects in a system design discussion.
Latency vs Throughput vs Bandwidth
Confusing latency and throughput is a common interview mistake. A system can have high throughput but high latency (batch processing), or low latency but.
Consistent Hashing
Consistent hashing is the backbone of distributed caching (Memcached), distributed databases (DynamoDB, Cassandra), load balancing, and CDNs.
CAP Theorem
CAP theorem is the most asked theoretical concept in system design interviews. It defines the fundamental constraint of distributed systems.
Failover
Without failover, any single component failure can bring down your entire system. Failover is how you achieve high availability in practice — it is the.
Fault Tolerance
In large-scale systems, component failures are not exceptions — they are the norm.
System Design Fundamentals
A comprehensive overview of what system design is, why it matters for every software engineer, and the foundational building blocks that every production.