Explain the concept of VLAN in networking.

VLAN stands for Virtual Local Area Network and is a method of logically segmenting a network. It allows the creation of multiple virtual LANs within a single physical network infrastructure. VLANs enable network administrators to group devices into separate broadcast domains, enhancing security, manageability, and efficiency. By dividing a large network into smaller VLANs, broadcast traffic is contained within each VLAN, reducing congestion and improving network performance. VLANs are configured through switches and routers, which assign ports to specific VLANs based on criteria such as port numbers, MAC addresses, or protocols.