Network Latency is the time it takes for a data packet to travel from its source to its destination across a network. Often measured in milliseconds (ms), it reflects the delay introduced during communication between devices, such as computers, servers, or IoT devices. High latency can result in noticeable lag in applications, particularly those that require real-time interaction, such as video conferencing, online gaming, or financial trading platforms.

Several factors contribute to network latency, including the physical distance between devices, the number of network hops (like routers or switches) along the path, and the type of transmission medium (e.g., fiber optics vs. satellite). Other technical causes include congestion, improper configurations, and hardware limitations.

Latency is often categorized into three main types: processing delay (time taken by devices to process packet headers), queuing delay (time packets spend waiting in queues), and transmission and propagation delay (time required to push bits onto the link and for the signal to travel). Together, these delays determine the overall round-trip time (RTT), which is a key metric for assessing latency.

Low network latency is crucial for delivering smooth and responsive user experiences. Organizations often invest in performance optimization techniques such as content delivery networks (CDNs), load balancing, and edge computing to reduce latency. Additionally, monitoring tools help identify bottlenecks and enable proactive improvements.