Get to Know Data Crawling, How It Works, and Its Types


Thanks to the advancement of today’s digital era, the amount of the available web data is increasing rapidly. However, most of the data is still random and unstructured. Therefore, data crawling is needed to index this data so that it is more structured, so that search engines can provide more relevant search results.

Data crawling is a data collection method that is used to index information using bots, namely crawlers which are often also referred to as web robots or web spiders. Basically speaking, crawling is an activity that is commonly done with search engines. The result of crawling is data that can be in the form of text, images, audio, and video. In general, web crawling is used by major search engines such as Google, Bing, Yahoo, statistical organizations, and large online aggregators.

How Does Web Crawling Work?

The web crawler starts the process by downloading the robot.txt file on the website. The file includes a sitemap that has a list of URLs for search engines to crawl.

After a web crawler starts crawling a web page, it will find new pages through the links on that page. This crawler will add the newly found URL to the crawl queue so that the crawling process can be carried out later. Thanks to this technique, web crawlers can index every page that links to other pages.

However, because these pages change regularly, it’s important to identify how often search engines crawl. Search engines use more than one algorithm to determine factors such as how often an existing page should be crawled and how many pages on a site should be indexed.

This crawling method that utilizes a web crawler or web spider is not only applied to search engines. The following are the types of data crawling that you need to know, including:

  1. Social Media Crawling

There are some social media platforms that allow web crawlers to browse pages on their platforms, as long as the pages do not reveal any personal information. However, some other social media do not allow crawling, because some types of crawling can be illegal and can violate data privacy.

  1. Video Crawling

Some people prefer watching videos rather than reading a lot of content on various sites. If YouTube videos or other video content is embedded on a website, then that content may also be indexed by some web crawlers.

  1. Image Crawling

This type of crawling is used to index images. As we know, images can be used for many things. So, this web spider can help us in finding images that match the user’s wishes from millions of images on numerous search engines.

  1. News Crawling

Since the advent of the internet, almost all news from around the world can be accessed quickly and easily. However, retrieving this data can certainly be inconvenient because the amount is so large. For that reason, this problem can be overcome by a web crawler by scanning information such as the publication date, author name, main paragraph, main title, and language of the news content. As a result, this crawler is able to retrieve data based on time, new, old and archived news content.

  1. Email Crawling

This type of crawling can be used to get leads by scanning email addresses. However, this practice can be considered illegal because it can violate privacy and cannot be used without the user’s permission.

That’s some information about data crawling that you need to know. If you want to know more about this activity, you can check out the following articles for further discussion.





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