Network latency refers to the delay that occurs when data is transmitted over a network. It is the time taken for a data packet to travel from the source to the destination and back again. Factors contributing to network latency include the distance between devices, the speed of the connection, and any processing delays at routers or switches. High network latency can lead to slow response times, affecting activities like online gaming, video conferencing, and web browsing. Reducing latency is important for improving user experience, and it can be achieved through optimizing network infrastructure and using faster connections, such as fiber optics.