Google crawler, also known as Googlebot, is an automated program that crawls and indexes web pages on the internet. It is responsible for finding new and updated web pages, adding them to the Google index, and providing them as results to user queries. In this way, Googlebot is the backbone of the Google search engine.
How Google Crawler Works:
- Discovery: Google Crawler starts its journey by visiting a few web pages that it knows from its previous crawl. These known pages often include some of the most popular and frequently updated websites on the internet.
- Following Links: Once on a web page, the crawler analyzes the page’s content and follows any links it finds to other web pages. This process is similar to how you navigate the web by clicking on links.
- Collecting Data: As Google Crawler visits web pages, it collects information about the page’s content, including text, images, and links. It also looks for new links to follow in the future.
- Storing Information: The data collected by the crawler is sent back to Google’s servers, where it is stored and processed. Google uses complex algorithms to determine the relevance and quality of the information on each page.
- Indexing: After analyzing the data, Google adds the web pages to its search index. This index is like a vast library catalog that allows Google to quickly retrieve relevant web pages when users search for specific terms.
- Ranking: When a user enters a search query, Google’s search algorithms use the index to determine which web pages are the most relevant to the query. These pages are then displayed in the search results, with the most relevant ones typically appearing at the top.
Here is a step-by-step example of how Googlebot works:
- Googlebot starts by identifying a list of URLs to crawl. It does this by following links from previously crawled pages or through a sitemap file.
- Once Googlebot has identified a URL to crawl, it sends a request to the web server hosting that URL.
- The web server responds to the request by sending the HTML code of the page to Googlebot.
- Googlebot then analyzes the HTML code to extract links to other pages that it has not yet crawled.
- If the page includes images, videos, or other multimedia content, Googlebot will also crawl these files and add them to the Google index.
- Googlebot analyzes the content of the page, including text, headings, and other elements, to understand what the page is about and how it relates to other pages on the web.
- Finally, Googlebot updates the Google index with the information it has gathered from the page and moves on to the next URL on its list.
Here is a screenshot of Google Search Console’s Coverage Report, which shows how many pages on a website have been crawled and indexed by Google:
Google Search Console Coverage Report
This report shows that out of 143 pages on the website, 142 have been crawled and indexed by Google, and only one page has an error preventing it from being indexed. The report also provides information about the types of issues that may be preventing certain pages from being indexed, such as server errors, page redirects, or blocked pages.
Overall, Googlebot plays a critical role in ensuring that the Google search engine can provide accurate and relevant search results to users. By understanding how Googlebot works, website owners can optimize their content and structure to increase the chances of being crawled and indexed by Google, ultimately leading to increased visibility and traffic.
