Local Area Network (LAN) is a group of computers connected to each other within a small area such as building or office via cable or wireless connections.
A Wide Area Network (WAN) is a network that spans over a large geographical area. It is not limited to a single location and extend across cities and national borders.
Virtual Private Network (VPN) allows users to create a secure connection to another network over the Internet. It helps users to protect their online privacy and maintain data security.
Intranet is a network that is used within a company by employees to communicate internally. An extranet network is designed for internal company use and allows external access to clients and vendors.