rch engine optimization (SEO) is the practice of getting targeted traffic to a website from a search engine’s organic rankings. Since organic search is one of the ways through which people discover content online, higher rankings can translate to higher organic traffic to a website.

SEO includes both technical and content practices aimed to align with the best search engine algorithm needs. Common tasks associated with SEO include creating high-quality content, optimizing content around specific keywords, and building backlinks.

In other words:

SEO is all about improving a site’s rankings in the organic (non-paid) section of the search results.

SEO is about improving a site's organic ranking

The main benefit of ranking for a specific keyword is that you can get “free” traffic to your site, month after month.

Organic traffic – Last 30 days

Here are the topics that we’ll cover in this complete guide to SEO:

How Search Engines Work

Now it’s time to learn how search engines like Google actually work.

How did you land on this result? Chances are you keyed in the search ‘What is SEO?’ or something along those lines, and the search engines did the rest.

When you search for something in Google (or any other search engine), an algorithm works in real-time to bring you what that search engine considers the “best” result.

Robot Scanning Numerous Websites

Specifically, Google scans its index of “hundreds of billions” of pages in order to find a set of results that will best answer your search.

How does Google determine the “best” result?

Google remains coy about its ranking metrics but based on expert research and a few hints from the search engines; crawlers or bots are used to gather information available on the internet. By using website navigation, read internal and external links, the bots understand the context of a page, and the search engines offer the pages with better visibility as best results.

Even though Google doesn’t make the inner workings of its algorithm public, based on filed patents and statements from Google, we know that websites and web pages are ranked based on:


If you search for “chocolate chip cookie recipes”, you don’t want to see web pages about truck tires.

Search relevance refers to the measure of the accuracy of the relationship between the search query and the intended search result. Domains with accurate, rapid, and relevant results get prominence from the search engines and hence rank top.

That’s why Google looks first and foremost for pages that are closely related to your keyword.

However, Google doesn’t simply rank “the most relevant pages at the top”. That’s because there are thousands (or even millions) of relevant pages for every search term.

For example, the keyword “cookie recipes” brings up 349 million results in Google:

"cookie recipes" – SERPs

Importance of Search Relevance

Imagine landing on a site and it provides a clear mismatch between your expectations and the search result. It implies such a site is both unprofessional and unreliable.

Statistica indicates a whopping 68% of people are unwilling to return to a site with poor search experience. In this regard, aim to build personalized, highly relevant, and target-driven content that meets search intent.

So to put the results in an order that bubbles the best to the top, they rely on three other elements of their algorithm:


Authority is just like it sounds: it’s Google’s way of determining if the content is accurate and trustworthy.

Authority refers to the overall influence and reputation a domain bears in a specific niche. Google considers the authoritativeness of a website based on its wider acceptance in the target niche.

The question is: how does Google know if a page is authoritative?

They look at the number of other pages that link to that page:

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