System Design Explanation 1

• latency — the time delay before a system responds.
• scalability — the ability of a system to handle more users or requests as it grows.
• throughput — the number of requests a system can handle in a given time.
• redundancy — extra components that provide backup in case of failure.
• hashing — creating a fixed-size code from data, often for lookups.
• collision — when two inputs create the same output in hashing.
• database index — a structure that speeds up searching in a database.
• fault tolerance — the ability to keep working even if parts fail.
• load balancing — distributing requests across servers to avoid overload.
• cache — temporary storage for frequently used data.

• handle high traffic
• store mappings in a database
• prevent collisions
• use caching for speed
• set up redundancy
• improve scalability
• balance the load
• reduce latency

• from the ground up — starting from the very beginning
• hit the limit — reach maximum capacity
• iron out the details — resolve small problems
• hold up under pressure — continue working well in a difficult situation

To design a URL shortener, I would first create a service that maps long URLs to short unique codes using hashing. These mappings would be stored in a database with indexes for fast lookups. When a user enters a short link, the system quickly redirects them to the original URL. To handle high traffic, I would use caching for popular links and load balancing across multiple servers. I’d also add redundancy and fault tolerance so the service keeps working even if some servers fail. This design reduces latency, scales as traffic grows, and ensures users always get redirected smoothly.