Network amplifiers are devices used to boost the strength of signals in a network, ensuring that data can travel longer distances without losing quality. They are commonly found in various types of networks, including Wi-Fi and Ethernet, where they help maintain a strong connection between devices. These amplifiers work by receiving weak signals and amplifying them before sending them out again. This process helps to reduce signal degradation caused by distance or obstacles, making them essential for maintaining reliable communication in both residential and commercial settings.