The resources in the internet are abundant, but it is a difficult job to search some useful information. So a search engine is the best method to solve this PRoblem. This article fist introdUCes the system structure of search engine based on the internet in detail, then gives a minute eXPlanation form Spider search, engine and web server. In order to understand the technology more deeply, I have programmed a news search engine by myself.
The news search engine is explained and searched according to hyperlink from a appointed web page, then indexs every searched information and adds it to the index database. Then after receiving the customers' requests from the web server, it soon searchs the right news form the index engine,
In the chapter of introducing search engine, it is not only elaborate the core technology, but also combine with the modern code,pictures included, easy to understand.
第一代搜索引擎出现于1994年。这类搜索引擎一般都索引少于1,000,000个网页,极少重新搜集网页并去刷新索引。而且其检索速度非常慢,一般都要等待10秒甚至更长的时间。在实现技术上也基本沿用较为成熟的IR(Information Retrieval)、网络、数据库等技术,相当于利用一些已有技术实现的一个WWW上的应用。在1994年3月到4月,网络爬虫World Web Worm (WWWW)平均天天承受大约1500次查询。