lagging

Lagging is the delay between an input and the corresponding output in a system, resulting in noticeable hesitation or slow response. The term is used across fields to describe slow or delayed reactions in digital and physical contexts, including computing, networking, gaming, streaming, and sometimes human activities.

In computing and networking, lag is often due to high latency, jitter, or limited bandwidth. Contributing factors include physical distance between client and server, network congestion, routing inefficiencies, packet loss, and server or device load. In interactive applications such as video games or video conferences, lag can reduce responsiveness, cause desynchronization between audio and video, and degrade overall experience.

Measurement and mitigation: Latency (ping) and round-trip time quantify lag, while jitter measures delay variation and throughput represents data rate. Mitigation strategies include optimizing software and hardware, improving network paths, reducing unnecessary traffic, employing caching and content delivery networks, and using quality of service or edge computing to shorten paths and balance load. For games and real-time applications, stabilizing frame rates and minimizing input-to-display delay are common goals.

In engineering and construction, lagging refers to insulating material applied around pipes, boilers, vessels, or ducts to reduce heat transfer and energy loss. Common materials include fiberglass and mineral wool; historically, some lagging used asbestos, which is now a hazardous substance and generally avoided or removed. Proper installation and moisture control are important to prevent heat loss, condensation, and mold growth.

Overall, lagging describes a delay or insulation-related performance aspect, with different implications depending on the field. See also latency, buffering, and insulation.