What Is SEO?
Search engine optimization explained: what SEO is, how search engines crawl, index and rank pages, and why it matters for your business.
SEO is one of the most talked-about topics in online marketing – and for good reason. With so much content online, a website that is not optimized is easily lost among thousands of others. Here are the basics.
SEO – a quick definition
SEO, or search engine optimization, is the process of continuously improving a website so that it ranks higher in search engine results pages (SERPs).
Traffic from search engines – organic traffic – is valuable because visitors are actively looking for what you offer, so they are more likely to become customers. When Google and other search engines can easily read and understand your content, they can rank it higher than your competitors’ content.
How SEO works
SEO helps people find your website when they search for specific keywords. Good optimization:
- helps search engines deliver relevant results
- gives people the information they are looking for
- brings more – and better – organic traffic
Search results appear instantly, but a complex process runs behind them, starting long before you type a query.
Crawling, indexing and ranking
For every search, a search engine relies on three main processes:
- Crawling – crawlers collect information from websites around the world, including all their pages and links.
- Indexing – the collected information is stored in a huge database called the index.
- Ranking – for each query, the results that best match it are shown in order.
To ensure quality results, search engines use algorithms – sets of rules that show people the most relevant information from trustworthy sources. Google has a dedicated team that keeps improving its algorithm. Some changes have names: Panda rewarded quality content and penalized thin content, Penguin targeted spam links, and Hummingbird improved how Google understands the meaning of queries. The message is always the same: Google’s top priority is great content.
SEO and AI search
Google’s AI features, such as AI Overviews and AI Mode, rely on the same ranking systems as classic search. Classic SEO therefore remains the foundation of visibility in AI answers. Read our SEO news →
Why SEO matters for businesses
A better-optimized website is more likely to rank higher – and the higher it ranks, the more people see and click it. Most searchers never go beyond the first page of results. When your website is near the top, customers find your business more easily, and SEO brings more qualified traffic: more leads, more sales and more profit.