System Design Overview Principles for designing systems that handle scale, remain available, and perform well under load. --- Scalability Fundamentals Vertical vs Horizontal Scaling Stateless Services --- Load Balancing Strategies | Strategy | Description | Use Case | |----------|-------------|----------| | Round Robin | Cycle through servers | Equal capacity servers | | Weighted RR | Based on server capacity | Mixed capacity | | Least Connections | Route to least busy | Long-lived connections | | IP Hash | Same IP → same server | Session stickiness | | URL Hash | Same URL → same server | Cac…