Shulou(Shulou.com)06/03 Report--

Today, I would like to talk to you about what is web crawler technology, many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

Web crawler technology refers to the technology that grabs the information of the World wide Web automatically according to certain rules. Web crawlers, also known as web spiders and web robots, are more often called web chasers in the FOAF community; other infrequently used names include ants, automatic indexing, simulators, or worms.

Web crawler technology refers to the technology that automatically grabs the information of the World wide Web according to certain rules.

Web crawler (also known as web spider, web robot, in the FOAF community, more often called web chaser), is a program or script that automatically grabs the information of the World wide Web according to certain rules. Other infrequently used names include ants, automatic indexing, simulators, or worms.

The description and definition of crawling target is the basis of how to determine the web page analysis algorithm and URL search strategy. The web page analysis algorithm and the candidate URL sorting algorithm are the key to determine the service form provided by the search engine and the crawler web page crawling behavior. The algorithms of these two parts are closely related.

The description of crawling targets by existing focus crawlers can be divided into three types: based on the characteristics of target web pages, based on target data patterns and based on domain concepts.

Based on the characteristics of target web pages

The objects crawled, stored and indexed by crawlers based on the characteristics of target web pages are generally websites or web pages. According to the method of obtaining seed samples, it can be divided into:

(1) pre-given initial capture seed sample

(2) the pre-given web page category and the seed samples corresponding to the category, such as Yahoo! Classification structure, etc.

(3) sample capture targets determined by user behavior, which can be divided into:

(a) grab samples that display annotations during user browsing

(B) access patterns and related samples are obtained through user log mining.

Among them, the web page feature can be the content feature of the web page, or the link structure feature of the web page, and so on.

Based on target data schema

The crawler based on the target data schema aims at the data on the web page, and the captured data generally conforms to a certain pattern, or can be transformed or mapped to the target data schema.

Based on domain concept

Another way of description is to establish an ontology or dictionary of the target domain, which is used to analyze the importance of different features in a topic from a semantic point of view.

After reading the above, do you have any further understanding of what is web crawler technology? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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