C/S模式是一种普遍应用的网络计算模式。传统的C/S模式是两层结构，在这种模式下，网络中的计算机分为两个有机部分：客户机和服务器。服务器只负责各种数据的处理和维护，为各个客户机应用程序管理数据；客户机包含文档处理软件、决策支持工具、数据查询等应用逻辑程序，通过网络使用SQL语言发送、请求和分析从服务器接收数据。(The C/S model is a ubiquitous network computing model. The traditional C/S model is a two-layer structure, in which the computer in the network is divided into two organic parts: the client and the server. The server is responsible for handling and maintaining all kinds of data, and managing data for each client application; The client includes application logic programs such as document processing software, decision support tools, data queries, and so on, using the network to send, request, and analyze data from the server using SQL language.)