What does snapshot mean?

Snapshots are also called "webpage snapshots". When a search engine includes a webpage, it backs up the webpage and stores it in its own server cache. When the user clicks the "webpage snapshot" link in the search engine, the search engine Display the web page content captured and saved by the Spider system at that time.

The operating environment of this article: Windows 7 system, Dell G3 computer.

When the search engine includes a web page, it backs up the web page and stores it in its own server cache. When the user clicks the "web page snapshot" link in the search engine, the search engine will crawl and save what the Spider system captured at that time. The content of the web page is displayed, which is called a "web page snapshot".

Since web page snapshots are stored in the search engine server, viewing web page snapshots is often faster than directly accessing web pages. In the web page snapshot, the search keywords are displayed in bright colors. Users can click on the bright keywords to directly find the location where the keyword appears, making it easier to quickly find the required information and improve search efficiency. When the searched web page is deleted or the link is invalid, you can use the web page snapshot to view the original content of the web page.

Principle

Why do we only need to enter the keywords we want to query in the search box of the search engine, and the search engine will immediately search for them on the vast Internet? All web pages containing keywords are captured in one go and presented in front of us. If you understand how search engines work, you won't think so. There are many hyperlinks on each webpage, which link to other webpages, and there are still many hyperlinks on these webpages, which can link to other webpages. In this way, the spider system of the search engine connects the Internet to A large number of web pages are gradually crawled.

Google, the big brother among search engines, takes its name from an almost insurmountable number in mathematics: googol. This number is 10 to the power of 100. The number is stored in its web database. One billion web pages, these web pages are captured and saved by the Net Spider system through the above method. All of these web pages, when displayed in search engine results, are called web snapshots.

Snapshot capture

When a user uses a search engine to search for a web page on the Internet, it is actually searching in the search engine's web page database. The user mistakenly thinks that the search engine All of a sudden, I found web pages containing keywords on the Internet.

Web pages on the Internet are not static, but are constantly being added, deleted, and modified. Therefore, the web pages in the search engine web database also need to be updated in time, which means re-copying the web pages on the Internet. If you delete a web page on your website, the copy - the web page snapshot in the search engine database will not be available immediately. be deleted, but it will take a while before being deleted. However, Google's web page snapshot indicates the snapshot archive time, so at this point in time, the web page must still exist. For example: Open a Google web page snapshot on July 20, 2008, and this snapshot shows that Google searched and archived it on July 10. What's the meaning? This means: on July 20, 2008, this webpage may have been deleted or updated, but on July 10, 2008, when Google copied and archived the webpage, the webpage did exist.

Search engines and snapshots

Search engines also try to collect all URLs that can be found, and also queue up web pages containing the same keywords. Purely commercial search engines Purely commercial principles are adopted, and web pages are ranked according to click-through rate, which ensures that users' search efficiency is maximized.

The search engine is just a tool. If you drive it skillfully, you can find very rich resources on the Internet.

At present, the most user-friendly web page snapshot is "Baidu", and "Baidu Snapshot" owns Google In addition to all the functions of Snapshot, it also adds a keyword positioning function to provide users with a faster and more efficient keyword search method. In terms of convenience, "Baidu Snapshot" greatly surpasses other similar search engines.

Function

The function of web page snapshot:

1. Web page snapshot can retain the content information before the web page is modified.

2. Web page snapshots can reflect the frequency of spiders crawling the website.

3. Web page snapshots can be used as a reference for existing website content and spider crawling content.

4. Web page snapshots can reflect the periodic content updates of the website.

5. Web page snapshots can reflect the level of search engine trust at this stage.

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