How A Search Engine Works


Crawlers are used to gather information about websites.


Crawler information is compiled and processed into a single database.


Queries are matched with relevant responses which come from the index.


Improve Ranking by proving to Search Engines your results are the most relevant.

Search Engines: Indexing, Crawling and Ranking

Search Engine’s revolve around automated data scrapers called “Spiders” or “Crawlers” to collect information about which is then indexed in the big Google book, and then finally ranked when queries arrive. Once websites have been ranked according to a very specific query (for example “what is a search engine”), the Index learns which websites are more clicked on than others, and thus Search Engine Optimisation becomes possible.

1. Crawling

  1. Crawler Arrives at Destination URL
  2. Crawler collects key HTML information
  3. Crawler detects images
  4. Crawler detects text
  5. Crawler finds linked pages
  6. Crawler navigates linked pages
  7. Crawler returns Home

Crawling is the process of automated data collection of websites, and domains. Crawlers quickly transverse the internet due to the interlinkages, allowing them to effectively create a “map” of the internet.

2. Indexing

  1. Crawler returns Home
  2. HTML information is stored
  3. Text is processed
  4. Images are processed
  5. Text & Images are stored
  6. Domain is mapped
  7. Penalties imposed

Indexing is the act of processing collected data and creating an understanding for a domain. Crawling and Indexing errors that occur from bad SEO are penalised.

3. Ranking

  1. A query is made (e.g. “technical SEO”)
  2. Index is scanned for relevant websites
  3. Ranking Algorithm
  4. Google displays most relevant answers
  5. User clicks and query is satisfied
  6. User does not click and process starts over

Queries are questions that are asked to google on a daily basis. When a query is made, Google scans its database (the index) for websites that may be relevant. Every single website that may be relevant is then ranked according to Google’s Hummingbird Algorithm, comprised of more than 1,000+ factors. The most relevant response is then presented to the query-maker as link #1, the second most relevant response is present as link #2, and so forth.

4. SEO

  1. Index learns which responses are better
  2. Your website is ranked lower or higher
  3. You become relevant for contingent keywords
  4. Your DA grows as you rank better
  5. Organic exposure increases tremendously
  6. User experience improves

Search Engine Optimisation is an organic way of improving your ranking on Search Engines like Google. SEO is in effect, abiding by the rules that Google likes the best, in order to remove penalties, provide the most value to a customer, and prove that your website is really important. Optimisation can be done in dozens of ways, these services exist to improve TECHNICAL SEO.

Crawling | Indexing | Ranking | SEO

Crawling is tracking and gathering URLs to prepare for indexing. By giving them a webpage as a starting point, they will trace all the valid links on those pages.

Digital Shift Media

Crawling and Indexing information is gathered from Search Console’s or Webmaster interfaces. Sitemaps are pre-created roadmaps that Crawlers follow to find things on your site. A good Sitemap makes indexing way easier, and Google loves that, so you’re far less likely to get penalised. Ranking, through Google at least occurs through the Hummingbird Algorithm which is largely powered by RankBrain, the new Google AI. This is all surmised in SEO, which is broken down into On-Page SEO, Off-Page SEO, and Technical SEO.

3 thoughts on “How A Search Engine Works”

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