The search engine can indeed provide any information you want quickly. However, do you know what allows that to happen? It is a web crawler.
This web crawler is responsible for making the search engine function properly and correctly. Its existence is indeed not widely known by many people, but its function cannot be underestimated.
What is Web Crawler?
Understanding web crawlers or often also called spiders is a tool to index and download content from the internet, then stored in a search engine database.
So that when someone searches for information, the search engine will immediately display relevant results from that database.
If you are still confused, try to imagine a librarian. The librarian is in charge of tidying up the books in the library so that visitors can easily find the book they are looking for.
These books are organized by category and topic of discussion. Thus, the librarian must look at the title and brief description of the book before placing it on the appropriate shelf.
Web crawlers collect / index any information that might be useful on the internet. From article content, images, videos, sounds to email addresses and RSS feeds.
Web Crawler Example
Every search engine on the Internet has its own web crawler. Therefore, if you do a search with the same keywords in other search engines will produce different results.
Some other web crawlers besides Googlebot are as follows:
- Bingbot from Bing
- Slurp Bot from Yahoo
- DuckDuckBot from DuckDuckGO
- Baiduspider from Baidu (search engine from China)
- Yandex Bot from Yandex (search engine from Russia)
- Sogou Spider from Sogou (search engine from China)
- Exabot from Exalead
- Alexa Crawler from Amazon
Google as the ruler of the search engine market share displays search results far better than other search engines. Therefore, you must prioritize your website being indexed by Googlebot.
How do crawlers work?
The internet is always changing and growing all the time. Because it is not possible to know the exact number of pages on the internet, this web crawler starts its work based on a list of links pages that it has previously known from a website’s sitemap.
Now, from the list of sitemap links, he will find other links scattered in it. After that, it will crawl to the links that have just been found. This process will be repeated again in the next link and can continue to run without stopping.
However, this web crawler does not carelessly do crawling. There are some rules they still have to obey, so they can be more selective in crawling. Usually in crawling, he considers three things:
How Important and Relevant a Page is
Web crawlers do not necessarily index everything on the internet. It determines which pages need crawling, based on the number of other pages that put a link to that page and the number of visitors to it.
So, if a page appears on many other pages and get a lot of visitors, chances are that page is indeed important.
This important page usually contains content or information needed by many people, so the search engines will definitely put it in an index so that people more easily access it.
The contents on the internet always change every second. Whether because of an update, deleted, or moved to another place. Therefore, web crawlers need to visit various web pages regularly to ensure the latest version of the page is in the index.
Especially if the page is an important page and many visitors, it is certain that it will often make regular return visits there.
Follow the wishes of Robots.txt
Web crawlers also determine which pages need to be crawled based on what robots.txt wants. So before crawling to a website, he will check the robots.txt from that website first.
Robots.txt is a file on a website that contains information about which pages should be indexed and which pages should not be.
Web Crawler function
The main function of web crawlers is to index content on the internet. But in addition to that, there are several other functions that are equally important:
1. Compare Prices
Web crawlers can compare prices of a product on the internet. So the price or data of the product can be accurate. So, when you search for a product, the price of the product will immediately appear without the need to go to the seller’s website.
2. Data for Analysis Tools
Website analysis tools such as Google Search Console and Screaming Frog SEO rely on web crawlers to collect data and index. So that the data generated is always accurate and up to date.
3. Data for Statistics
Web crawlers also provide important data that can be used for news websites or statistical websites. For example, news search results that will appear on Google News. To appear on Google News, the website requires a special sitemap that will be crawled by web crawlers later.
What is the effect of web crawlers on SEO?
Web crawler is a tool that functions to do crawling and indexing. Well, if he does not index your website, then your website will not appear in search results. If the website doesn’t even appear in the search results, it’s impossible to get the top position in the search results.
So in other words, before you do any SEO tactics, make sure your website is indexed first.
Block Web Crawlers
As mentioned above, you can block or ban web crawlers from crawling using robots.txt.
Why is it blocked? Because, under certain conditions, there is content that does not need to be indexed. For example, duplicate content. This duplicate content can actually make your website removed from the index. Therefore, this duplicate content should not be indexed by web crawlers.
In addition, banning web crawlers from crawling unnecessary pages can reduce your website’s load and speed up the indexing process.
For a tool that works behind the scenes without stopping, this web crawler provides many benefits, right?
After knowing the many benefits, you definitely want web crawlers to index your website. Now, to make a web crawler indexing your website, then you need to optimize your website. Both from the aspects of SEO, design, to the responsiveness of your website.