What is a web crawler?

It’s a common experience that happens millions of times a day, and most people take it for granted. You enter a few words in an online search box to find something you want, for instance, a product on an ecommerce website, and voila! It seems to materialize out of thin air. 

But what’s behind the curtain making everything happen so magically? What’s powering that seemingly supercharged search engine?

Web crawlers for digital content

Answer: a website crawler: the hard-working, lesser-known, essential component of a search engine. A web crawler is a bota software programthat systematically visits a website, or sites, and catalogs the data it finds. It’s a figurative bug that methodically locates, chews on, digests, and stores digital content to help create a searchable index. 

Web crawlers work behind the scenes, but they play a critical role. Without crawlersand there are thousands of them around the worldthere would be no instant provision of relevant search results, no easy discovery of desired information and product data.  That’s especially important given that, according to Forbes, as much as 90% of the world’s data is “unstructured.” It’s a digital jungle out there. Companies must determine how to organize and manage a growing amount of digital material so that they can both create elegant online user experiences and quickly find internal business information.

Web spiders of many species

There are several types of web crawler. 

Some are dedicated to collecting and indexing data found on the entire Internet. You’ve undoubtedly heard of Google’s infamous Googlebot. The company also has “subbot” spiders that collect specific types of information. There’s also Bingbot for Microsoft Bing; Baidu Spider, the main web crawler in China; and the Russian web crawler, Yandex.

In addition to the relatively few celebrated whole-Web crawlers, there are tons of smaller and less famous ones creeping unceremoniously across certain segments of the Web.

Content-specific crawling

Some web crawlers are used for gathering only certain types of content, such as email, videos, or images. Googlebot Video and Social Media Crawler are examples of these.

Some crawlers work not only by gathering and organizing content from websites or apps, but from across the world of ecommerce: they can extract specified product information that people need in order to find the right products and make purchasing decisions.

Single-site spiders

Some website crawlers are designed to be used with content on a particular website. 

  • The Octoparse crawler lets you extract data from a site without doing any coding
  • HTTrack Website Copier, a free utility, can download an entire site to a local directory on your computer
  • The customizable and configurable Algolia Crawler can enrich extracted content with business data to enhance the relevance of the user experience

Specialized spiders

Other crawlers are dedicated to particular types of usability and functionality. For example:

  • The Screaming Frog SEO Spider is all about improving companies’ search engine optimization (SEO) for website content 
  • Do you need to crawl content in Java? You can use GitHub’s open-source crawler4j 
  • If you want to get your digital hands on data from sites that use Ajax, JavaScript, or cookies, you could consider Parsehub 

The fruits of crawlers’ labor

If we didn’t have web crawlers, search engines would have no idea that websites have newly available or updated content. Plus, website crawling, extracting, and structuring provides a multitude of other benefits. 

When a web crawler makes it easy for a search engine to understand and accurately represent what’s on your site, you’re closer to getting the right content or product to prospective customers. 

When an ecommerce site makes its product descriptions, images, reviews, and buying information easily discoverable, it’s one step closer to maximizing relevancy and revenue. Information that’s up to date—and immediately available—is indeed powerful.

Crawlers can also surface more information, thereby enriching search results, through their combing of “hidden” content such as metadata, usage data, tags, and relevancy signals.

What to look for in a website crawler

When you’re on the hunt for the perfect website crawler, whether it’s for a website with written content, an application with media content, or an ecommerce store, it can be easy to get overwhelmed by all your options (which, of course, you’ll learn about thanks to the efforts of web crawlers). 

To narrow your search, focus on making sure your new crawler will be all of these things:

Effective. The crawler of your dreams will expertly extract and structure your website content, making it easily deliverable to your visitors and customers, with all of the attendant profit-related benefits that may hold.

Customizable. Regardless of the type of website you have, you want to be able to tailor crawler operations to make sure your spider accurately interprets your unique content and meets your business needs. For instance, you might want crawling to automatically commence at certain times of the day. You might need only certain parts of your site crawled. Your crawler needs to meet your unique data-extraction needs, and to be effortlessly adaptable.

Scalable. If you’re looking to build your business and expand content or product offerings on your site, you need a crawler that can efficiently scale with your organization’s growth and evolving business requirements. 

Production ready. Your crawler should include digital tools that let you imbue users’ search experiences with accurate, timely information. For example, the crawler you select should include a data analysis tool that lets you assess the quality of what your crawler digs up. And it should include a data-monitoring tool that tells you about any errors found during the crawling process.

That’s crawl, folks

Congratulations; you now know some of the key facts about, functions of, and possible features included with the world’s many and varied website crawlers. 

You know the inherent value that web crawling can provide for a business. You understand how a crawler can streamline website operations, quickly get the right information to the right visitors or prospective customers when they request it, and ultimately create better user experiences, increase revenue, and facilitate wide-ranging success. 

And if you have an ecommerce site, you no doubt realize the implications of putting this essential data-gathering tool to work on your company’s behalf, and doing it as efficiently as possible. 

The search is on for your perfect web crawler. Which one will you choose?

Using a crawler to create a leading digital UX

In researching your crawler options, we hope you’ll check out Algolia’s. Our search-as-a-service platform enables companies of all sizes, in countries around the globe, to provide consumers with fast, relevant digital experiences that drive results.

What’s unique about our hosted crawler is that it works across business sectors and industries, including digital media, ecommerce marketplaces, and more. We’ve helped many companies in the Fortune 500, as well as medium-sized organizations and small businesses, create leading digital experiences.

Here are some ways Algolia can help your company unleash your content.

Intrigued? Check out this in-depth webinar on how our crawler can help your business succeed.

Thank you for reading, let us know if you have any questions, and good luck with your web crawler search!

About the authorCatherine Dee

Catherine Dee

Search and Discovery writer

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