局域网提供在特定的建筑物或设备范围内的通信。比方说,这种类型的网络可以应用于一个在销售、财会、生产和采购部门都有计算机的公司里。每台计算机只处理本部门的工作。当计算机之间需要进行通信时,计算机可以通过网络互相传递数据。例如,采购信息必须传送到财会部门,以便记入帐目支付系统;或者生产计划信息必须传送到采购部门,以便采购和存货系统使 LANs provide communications within a specific building or device range. For example, this type of network can be applied to a company that has computers in the sales, accounting, production, and purchasing departments. Each computer only handles the work of this department. When computers need to communicate, computers can transfer data to each other over the network. For example, procurement information must be transmitted to the accounting department for entry into the account payment system; or production planning information must be transmitted to the purchasing department for procurement and inventory systems.