In the ever-changing digital landscape, understanding how crawlers work has become an essential skill for webmasters and SEOs. These automated programs, also known as web crawlers, play a crucial role in indexing websites and optimizing their visibility in search engines.

Design by Freepik 

By crawling websites and following hyperlinks, crawlers collect information about the content, structure and quality of each page. This information is then used to determine a website's ranking and relevance in search results. A better understanding of how crawlers work allows webmasters and SEOs to optimize their websites for more efficient crawling. This can lead to better visibility, more organic traffic and increased conversions.

 

The different types of crawlers

There are different types of crawlers, each with their own specific goals and features:

• Search Engine Crawlers: These crawlers are the most common and are used by search engines like Google, Bing and Yahoo to discover and index new web pages. They are responsible for building the vast search indexes that allow users to find relevant information on the web.
• Website Crawlers: These crawlers are used by website owners to explore their own site and identify possible technical problems, such as broken links or inaccessible pages. They can also be used to collect data about site traffic and performance.
• Social Media Crawlers: These crawlers crawl social networks like Facebook, Twitter and Instagram to collect data on shares, likes and comments. This data can be used to analyze trends and audience engagement.
• Prize Crawlers: These crawlers crawl e-commerce websites to collect product pricing information. This data can be used to compare prices and find the best deals.
• Data Crawlers: These crawlers crawl specific websites to extract structured data, such as product listings, events or financial information. This data can be used for various purposes, such as market analysis or competitive research.

 

The exploration process by a crawler

The exploration process by a crawler can be broken down into several key steps:

1. Discovery of the web page: The crawler discovers a new web page either by following a link from an already indexed page or by submitting the page's URL to the search engine.
2. Downloading the web page: The crawler downloads the HTML code of the web page from the web server.
3. Content analysis: The crawler analyzes the content of the web page to extract information such as the title, meta description, main text and keywords.
4. Link Tracking: The crawler identifies hyperlinks in the web page and adds them to its list of pages to crawl later.
5. Indexing of the web page: The crawler stores the information extracted from the web page in the search engine index.
6. Index update: The crawler updates the search engine index to reflect changes made to the web page.

 

Factors influencing crawler behavior

Several factors can influence the behavior of a crawler when exploring a website:

• Website structure: A website with a clear, hierarchical structure is easier for crawlers to crawl than a website with a complex or disorganized structure.
• Robots.txt file: The robots.txt file is a text file that website owners can use to tell crawlers which pages to crawl and which not to crawl.
• Page loading speed: The page loading speed of a website can affect the ability of crawlers to crawl the site effectively.
• Content quality: The quality of a website's content can also influence the behavior of crawlers. Crawlers are more likely to stay on a page and follow its links if the content is relevant, informative and useful.
• Freshness of content: Crawlers give more importance to websites that regularly publish fresh and relevant content. By regularly updating your website with new content, you encourage crawlers to come back more often and explore your new pages.
• Mobile-friendliness: With the increase in the use of smartphones and tablets to browse the web, search engines are placing increasing importance on the mobile compatibility of websites. A responsive website that displays correctly on all devices is more likely to be crawled effectively by mobile crawlers.
• Technical errors: Technical errors on a website, such as broken links, erroneous pages or redirection issues, can hinder crawlers' crawling. By identifying and correcting these technical errors, you make their work easier and improve the user experience.
• Crawl budget: Search engines have a crawl budget allocated to each website. This budget determines how often a crawler will visit your site. Several factors can influence the crawl budget allocated to your site. This includes the size and complexity of your site, how often your content is updated, and the overall quality of your website.

 

The impact of crawlers on SEO

Crawlers play a crucial role in SEO. Indeed, they determine the ability of a website to be indexed and ranked in search results. A website that is not properly crawled by crawlers will not be indexed by search engines and will therefore not be able to appear in search results. By optimizing your website for better crawling by crawlers, you can improve its visibility in search engines and attract more organic traffic.

Here are some ways that crawler optimization can improve your SEO:

• Ranking Improvement: By making it easier for crawlers to crawl and index your website, you increase the chances that your web pages will be ranked higher in search results.
• Increase in organic traffic: Ranking higher in search results usually results in increased organic traffic to your website.
• Improved user experience: A website optimized for crawlers is often also more user-friendly. By ensuring your website is easy to navigate and explore, you improve the overall user experience.

 

Tools and techniques for analyzing crawler activity

Several tools and techniques allow you to analyze crawler activity on a website:

• Google Search Console: This free tool from Google provides valuable information about crawler activity on your website, including the number of pages crawled, errors encountered, average page load time and inbound links. By analyzing this data, you can identify potential issues hindering the crawling of your website and take corrective action.
• Screaming Frog SEO Spider: This paid tool is a popular website crawling tool that helps identify common technical issues that can hinder crawlers' crawling, such as broken links, erroneous pages, and redirection issues. Screaming Frog also provides valuable information about the structure of your website and the presence of important meta tags.
• Server log files: Server log files contain detailed information about incoming traffic to your website, including crawler requests. By analyzing these log files, you can identify which crawlers visit your website, how often they visit, and which pages they crawl.
• SEMrush and Ahrefs: These paid SEO tools offer advanced crawl analysis features, including the ability to track your website's crawl history and compare your website to your competitors.

 

How crawlers work in brief

By understanding how they work and optimizing your website for better crawling, you can improve its SEO and visibility in search engines. This will allow your website to reach a wider audience and attract more organic visitors. Don't forget to check out the recommended resources to deepen your knowledge of crawlers.

 

 

Esteban Irschfeld, SEO Consultant at UX-Republic