Search Engines: How do they work?

Before talking about search engine optimization, we must understand what a search engine is. Most people know that Google and Bing and search engines, but let’s dig a little further past the basics and into the functions of crawling and indexing. The major functions of search engines serve the purpose of delivering results quickly to users.

Crawling is nothing more than going from one link to the next, searching through the billions of pages, videos, media, and so on that exist online. After crawling, indexing happens, meaning that all those previously crawled documents and files are filtered and indexed according to the importance perceived by the search engine.

It’s precisely by doing this that search engines have the capacity to rank the websites in a list ordered by relevance, allowing the user who performed the search to access the most relevant sites.

Crawling and Indexing

To understand the crawling process we can imagine the internet like if it is a subway network, and each subway stop is a document, a web page, an image, a PDF or other file. The job of the search engine is to crawl through the whole subway network, to see all the stops, to see all the documents.

Crawling is performed by bots. These robots, or crawlers, or spiders, whatever we want to call them, are the ones that reach the billions of documents on the web through the existing links. After crawling, indexing happens, meaning that the crawling has a memory that lists where each stop or document is, and the result of this memory or indexing are the well-known links, the paths between different sites or documents.

Link Structure

Similarly to the links on a web page, the whole internet is linked together, and search engines have a map with all those links and connections. Once the search engines find the pages, they analyze their code and store the relevant content in databases.

Needless to say that those huge databases are precisely the ones being accessed whenever anyone makes a search on the Google or other search engine interface.

– “This is where the term, “the web” comes from. Each link on the internet is connected, as the entire internet is one interconnected web of “webpages

Giving answers

Expecting a result in seconds is something common for us, but if we stop to think about the massive task that it is to go through 30 trillion documents, listing them in fractions of a second, we realize it’s not something simple to achieve. There is a lot of technology behind it.

To accomplish that, Google, Microsoft, and others have data centers spread throughout the world. Those are not common data centers, but storage facilities with thousands and thousands of machines capable of processing huge quantities of information very fast.

On the internet, we have come to expect answers on the spot, and sometimes if we have to wait a few seconds we might even think that a site is slow, but that rarely happens with Google or other major search engines. They don’t disappoint, and that is why everyone uses them. They are reliable and work hard to maintain the same level of service. This is why they have come to dominate the search engine market. Often when people speak of seo, they are really only including Google as they hold almost 80% of the US market when it comes to internet searches.

Relevance and Popularity

Making a search is making a request to an answering machine that will go through all those documents and returns the ones relevant to our query, but the returned results are organized by the relevance and quality of the sites that have the type of content we are looking for.

SEO aims to influence, therefore, relevance + popularity.

These are not just any search machines that look for certain words though, no. When the internet begun, not that many years ago, most likely it was something like that, but these days the process has evolved to a whole new level. Evolution of technology and experience in the area made possible better ways to associate results with queries.

Mathematic equations

It’s no simple formula though. It’s so complex that it’s even called an algorithm, and involves hundreds of factors, but in the end, the search engine basically assumes that the more popular a site or document is, the more value it has.

The word algorithm actually has a mathematical meaning, what is the same thing to say that when we talk about relevance and popularity, we are talking about mathematical results, and not something determined manually.

Those mathematical equations used by search engines to rank sites by quality have hundreds of variables or ranking factors that, needless to say, many are kept in the secret.

Succeeding in Search Engine Optimization

Like we mentioned in the introduction of this guide, it doesn’t really matter how impenetrable the algorithms used by search engines are, what does matter is the quality of our site.

Search engines do give us a helping hand though, as they indicate best practices we should use to best optimize our sites, to achieve the best results possible. So, if the search engine creators give us SEO tips, it just seems common sense to follow those.

Google SEO Guidelines

If we want to improve the results of our site in Google, here are some tips directly from the source:

1. Our pages should be made for users, not made for search engines. This is basic, but it’s also a stepping stone to the success of SEO. A page aimed at user experience will have more chances of being included in the top search results, pretty much the same way as a quality product has more chances of being bought by customers vs one that is just packaged nicely.

2. Make a clean and clear structure of links. The pages of the site should be easily accessible.

3. Create quality content, an informative site, and create pages that describe that content clearly. Titles, elements, and attributes should be accurate.

4. Create friendly URLs with the use of keywords.

Bing SEO Guidelines

Other search engine creators like Bing also have their SEO tips, and they are not that different from the ones provided by Google:

1. Clean URL structure

2. Don’t hide the contents on rich media like Adobe Flash or Javascript, making sure that the links aren’t hidden from the crawlers

3. Create rich and quality content with popular keywords, as well as new content regularly

4. If we want certain content to be indexed, that content should not be inside images or else that indexation might not happen

It’s all about Marketing

There are additional guidelines we can follow apart from the ones offered by the search engines. SEO has existed for some years now, and during this time many have studied it, and have extracted valuable information regarding the way search engines rank pages. Surprisingly or not, search engines hold conferences on marketing search to help marketing experts in their SEO endeavors.

The Experiment

Progress is often based on experience, but this experience can be acquired by learning from other webmasters in SEO. It is often necessary for one to experiment with search engines in order to see how they respond. It’s a trial and error process, a constant and scientific base of hypothesis testing.

The truth is, there’s a community of marketers that analyze search engines and websites to determine why some pages get better rankings and more traffic than others, and along with reading this guide, joining and learning from these communities is another step forward in the right direction.

Skip to toolbar