Latency refers to the delay between a user's action and the response from a system. In computing, it is the time taken for data to travel from one point to another, such as from a user's device to a server and back. High latency can lead to noticeable delays, affecting the performance of applications like online gaming or video streaming. In networking, latency is often measured in milliseconds (ms) and can be influenced by various factors, including the distance between devices, the type of connection (like Wi-Fi or fiber optics), and network congestion. Reducing latency is crucial for improving user experience in real-time applications.