Manually collected search engines include directory search engines, keyword full-text search engines and meta-search engines.

This information is not retrieved instantly from the Internet by search engines. What is commonly called a search engine is actually an online database that collects a large number of website/webpage materials and indexes them according to certain rules, such as 2004 By the end of March this year, the number of web pages included in Google had exceeded 4.2 billion. In this way, users can feedback a large number of results in a short period of time when searching.

Manually collected search engine real-time search:

The real-time requirements for search engines are increasing day by day, which is also a future development direction of search engines.

The most prominent feature of real-time search is its strong timeliness. More and more emergencies are published on Weibo for the first time. The core of real-time search is "fast", and the information released by users is the first time Can be found by search engines. However, in China, real-time search cannot be widely used due to various reasons. For example, Google's real-time search has been reset, and Baidu does not have an obvious real-time search entrance.

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