鳥取県

By: Sexy

On: November 13, 2025

鳥取県（とっとりけん）は、日本の中国地方（山陰地方）にある県である。県庁所在地および最大都市は鳥取市。日本海側にあり、山陰地方の東側を占める。面積は約3,507平方キロメートルと全国で7番目に小さく、人口は約52万人と都道府県別で最も少ない。基礎自治体は4市14町1村で、市の数も最も少ない。

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Spider

Web crawler, sometimes called a spider or spiderbot and often shortened to crawler, is an Internet bot that systematically browses the World Wide Web and that is typically operated by search engines for the purpose of Web indexing (web spidering).

Web search engines and some other websites use Web crawling or spidering software to update their web content or indices of other sites' web content. Web crawlers copy pages for processing by a search engine, which indexes the downloaded pages so that users can search more efficiently.

Crawlers consume resources on visited systems and often visit sites unprompted. Issues of schedule, load, and "politeness" come into play when large collections of pages are accessed. Mechanisms exist for public sites not wishing to be crawled to make this known to the crawling agent. For example, including a robots.txt file can request bots to index only parts of a website, or nothing at all.

The number of Internet pages is extremely large; even the largest crawlers fall short of making a complete index. For this reason, search engines struggled to give relevant search results in the early years of the World Wide Web, before 2000. Today, relevant results are given almost instantly.

Crawlers can validate hyperlinks and HTML code. They can also be used for web scraping and data-driven programming.