What is SEO and how does it work?

A simple definition of SEO

SEO stands for search engine optimisation. In practice, it's everything that makes a page on your website easy for Google to find, read and choose when someone is looking for a product, a service or an answer. It isn't advertising and there's no fee for a position. It's ongoing work on the technical quality, content and reputation of a website.

A good starting point is three questions a search engine asks about every page: can I access this page, do I understand what it's about, and is there a reason to rank it above the alternatives? When all three answers are yes, you get visibility. When the first one fails, nothing else matters.

How Google discovers and ranks websites

The process has three distinct stages, and it's worth separating them, because most real problems happen at the first or second one.

1. 1Crawling: automated programs follow links and read the code of pages. If a page isn't linked from anywhere and isn't in the sitemap, it may simply never be visited.
2. 2Indexing: the search engine stores and organises what it has read. A page can be crawled and still not be indexed, for example if it's blocked, duplicated or has no original content.
3. 3Ranking: for each search, the system picks the indexed pages that best match the searcher's intent, taking into account relevance, quality of experience, trust signals and context such as language and location.

The four areas of SEO work

1. Technical SEO

This is the foundation. It includes a clean URL structure, correct sitemap and robots files, unique titles and descriptions, structured data where it makes sense, working mobile versions, HTTPS, proper redirects and healthy load times. Without this foundation, the rest of the investment delivers less. Load speed is covered in detail in slow websites and their impact on Google and sales.

2. Content

Every page should answer a specific intent. A service page answers someone ready to hire, a guide answers someone trying to understand, a pricing page answers someone comparing options. Useful content means original explanations, real examples, clear terms and enough information for people to decide without leaving the site.

3. Authority

Google uses external references as a trust signal. Links from quality directories, industry associations, local press, partners and clients all help. Buying link packages is an unnecessary risk and a waste of budget.

4. Local SEO

For businesses serving customers in a specific area, local SEO is usually the fastest lever. It covers your Google Business profile, consistent contact details, pages per service area and reviews. We've written a dedicated guide for the Portuguese market in local SEO in Portugal.

How long does SEO take to show results?

It depends on competition, the current state of the website and how consistently the work is done. Technical fixes can show effect within days or weeks. New content on topics with demand usually needs a few months to settle. In highly competitive sectors, a serious plan is measured in quarters, not weeks. Any promise of a first position by a fixed date should be treated with suspicion, because no one controls the algorithm or the competition.

SEO or paid advertising?

They aren't mutually exclusive. Advertising buys immediate visibility and stops the moment the budget does. SEO builds visibility that lasts, but it takes time. Many businesses start with campaigns to generate demand while SEO matures.

The full comparison, with decision criteria, is in Google Ads or SEO. How campaigns work is explained in what is SEA.

Common misconceptions

• Repeating a keyword many times improves ranking. It doesn't, and it harms readability.
• Submitting your site to Google once is enough. Submission helps with discovery, it doesn't guarantee indexing or ranking.
• Guaranteed rankings exist. No one can legitimately guarantee them.
• SEO is a one-off project. The market, competitors and the search engine itself keep changing.
• More pages is always better. Weak, repetitive pages dilute a site.

When it makes sense to hire professional SEO

It makes sense when there's genuine demand for what you sell, when the value of a customer justifies the investment, and when someone in the business is available to validate technical, industry-specific information. If the website still doesn't convert visits into enquiries, it's worth fixing that first, because more traffic to a weak page still won't produce customers.