Latency is the amount of time it takes for data to travel from one point in a system to another. In networking, it measures the delay between sending a packet and receiving a response. High latency makes applications feel slow because actions take longer to complete. Latency is influenced by distance, routing paths, congestion, and server processing time. Many real time systems require low latency to feel responsive. Developers must balance latency with bandwidth, workload distribution, and caching strategies. Latency affects both frontend and backend performance.
key characteristics
Latency is measured in milliseconds and can vary throughout the day based on network traffic. Caching reduces latency by storing frequently used data closer to the user. CDNs improve latency by serving static assets from nearby locations. Backend latency accumulates from database queries, middleware, and application logic. Tools like tracing and logging help identify where latency originates. Understanding latency is essential when diagnosing slow pages, API calls, or user interactions.