Network latency refers to the time taken for data packets to travel from their source to their destination across a network, measured in milliseconds. It is influenced by factors such as distance between source and destination, network congestion, quality of network connections, and transmission mediums. High latency can lead to noticeable delays affecting online applications and services. Various methods are used to measure network latency, including ping, traceroute, network monitoring tools, application performance monitoring (APM) tools, speed test websites, and synthetic transactions. Reducing network latency involves addressing factors like propagation delay, transmission mediums, router and switch processing time, traffic congestion, network type, bandwidth limitations, quality of service settings, and server/host processing time.