What Is SEO? Getting Started with Search Engine Optimization

SEO in one sentence

Search engine optimization (SEO) covers all the measures that make your website easier to find in the unpaid search results – on Google, Bing, and increasingly in AI systems like ChatGPT, Perplexity, or the AI Overviews right inside Google Search.

Unlike with ads, you do not pay per click. Instead you invest in content, technology, and reputation – and thereby build a channel that delivers visitors for years. That is exactly what makes SEO one of the most profitable marketing channels: today’s work pays off tomorrow, in a year, and often still in five years.

A higher placement brings more visitors. More visitors bring more conversions – sales, newsletter sign-ups, inquiries. And because users are actively searching for your topic, this traffic is not only free but also especially qualified.

SEO vs. SEA: the difference

In the search results two worlds compete: paid ads (SEA, e.g. Google Ads) and organic results (SEO). Ads usually appear at the top and are labeled as “Ad” or “Sponsored”. The organic results below them are chosen by Google purely on relevance, authority, and quality – you cannot pay for that. SEO works exclusively on this organic area.

Both together are called search engine marketing (SEM). Ads deliver fast visibility, SEO lasting success – and users demonstrably place more trust in organic results.

How search engines find your page

When someone searches, Google does not comb the whole web in real time. It accesses a prepared index – a huge library of pages already discovered. The path there runs in three phases:

1. Crawling: Automated programs (crawlers or bots) follow links from page to page and discover new or updated content.
2. Indexing: Google analyzes a page’s text, images, and structure and stores it in the index. Only indexed pages can rank at all.
3. Ranking: For a search query, the algorithm sorts the matching pages by relevance and quality – the result is the search engine results pages (SERPs).

AI search systems today use the same mechanism: they access an index, evaluate sources, and cite the most trustworthy ones. Anyone who is cleanly crawlable for Google and thematically clear is also more likely to be found by LLMs. How this works in detail you can read in the article How search engines work.

The three pillars of search engine optimization

SEO rests on three pillars that interlock:

1. Technology: Your website must be crawlable, fast, and usable on mobile. Without a technical foundation, every piece of content fizzles out. More on this under Technical SEO.
2. Content: Content that answers search intents better than the competition – the heart of every strategy. The basis is clean keyword research and content that ranks.
3. Authority: References and mentions from other relevant websites signal that your content is trustworthy – the core of off-page SEO and link building.

A technically perfect page without good content does not rank. And the best content is useless if Google cannot crawl it. Only the interplay brings results.

What decides a ranking

The exact algorithms are a trade secret. The load-bearing principles, however, are known:

• Relevance: Does the page fit the search query thematically? Today Google understands whole topics and contexts, not just individual words.
• Authority: How trustworthy is the page? High-quality backlinks from topically relevant websites work like recommendations.
• User-friendliness: Loading speed (Core Web Vitals), mobile-friendliness, HTTPS encryption, and a clear layout all feed into the user experience – and thus into the ranking.
• Content quality: Does the page really fulfill the search intent and offer genuine added value? Google rewards helpful, trustworthy content in the sense of E-E-A-T.

The three types of SEO

In practice, SEO splits into three closely interlocked areas:

• On-page SEO – everything on your own page: keywords, title tags and meta descriptions, heading structure, internal linking, image optimization, and readability.
• Technical SEO – the foundation: crawlable structure, robots.txt and XML sitemaps, loading speed, mobile-first, structured data.
• Off-page SEO – everything outside your page: above all link building, plus brand mentions, social signals, and online reviews.

First steps with SEO

Getting started looks daunting, but with a clear plan it is doable:

1. Keyword research: Understand what your audience is searching for – and with which search intent (informational, navigational, commercial, transactional).
2. Create high-quality content: Answer your audience’s questions better than the competition.
3. Optimize on-page: Set up title, meta description, headings, internal links, and images cleanly.
4. Check the technology: mobile-friendly, fast, secure, crawlable.
5. Build authority: win high-quality backlinks from relevant websites.
6. Measure success: With Google Search Console you can see which search queries you appear for and how often you get clicked. Google Analytics 4 (GA4) shows where your visitors come from and what they do.

SEO is not a one-time task but a continuous process. Measure your results, learn from the data, and adjust your strategy.

Conclusion

SEO increases your website’s visibility in the organic results – through technical, content, and external measures. The algorithms change constantly, and with AI search a new layer is added. The basic principles, however, stay the same: relevance, authority, and user-friendliness. Whoever works patiently and strategically on these three levers lays the foundation for lasting success.