A network segment is a portion of a computer network that is divided to improve performance and manageability. Each segment can operate independently, allowing for better control of data traffic and reducing congestion. This division can be achieved through various methods, such as using routers or switches. By segmenting a network, organizations can enhance security and isolate issues more effectively. For example, if one segment experiences a problem, it won't necessarily affect the entire network. This approach is commonly used in larger networks, where different departments or functions may require distinct segments for optimal operation.