SEO (Search Engine Optimisation) is the set of techniques and practices that make a website more visible in the results of Google, Bing and the other search engines. Put simply: SEO is the reason one site shows up on page one and another on page twenty. And since over 90% of clicks go to the first 10 results, SEO is the difference between a website that brings in customers and one that gathers dust.
In this article we look in depth at what SEO is, how the Google algorithm works, what the three core components of optimisation are, which mistakes are the most common, and how long it realistically takes to see results.
How Google works — a short explanation
Google runs three core processes: crawling, indexing and ranking. Google's robots (known as Googlebot) crawl billions of pages, analyse their content and store it in an enormous database. When someone searches, the algorithm weighs hundreds of factors and, in a fraction of a second, orders the most relevant results.
Among the most important factors are:
- Relevance — how precisely the content answers the search query.
- Content quality — depth, originality, expertise (E-E-A-T).
- Technical factors — speed, mobile compatibility, security (HTTPS).
- User experience — time on page, bounce rate, interactions.
- Domain authority — quality backlinks from other websites.
On-page SEO — the foundation of everything
On-page SEO covers everything you can optimise directly within the pages of your own website. It is the most controllable part of SEO and the part every business should start with.
- Title tags — 50–60 characters, with the keyword up front.
- Meta descriptions — 150–160 characters, with a hook or benefit that earns the click.
- Headings H1–H6 — a hierarchical structure, with keywords in the H1 and H2.
- URL structure — short, descriptive URLs without unnecessary parameters.
- Internal linking — logical connections between related pages.
- Image alt attributes — descriptions for the crawlers and for accessibility.
- Quality content — at least 800–1500 words on your important pages, with real value.
Technical SEO — the invisible half
Even with the best content in the world, if your website is slow, broken on mobile or insecure, Google will not rank you highly. Technical SEO takes care of that infrastructure:
- Loading speed — must stay under 2.5 seconds for LCP (Largest Contentful Paint).
- Mobile-first indexing — Google judges the mobile version of your site above all else.
- Schema.org structured data — Article, Product, LocalBusiness, FAQ, BreadcrumbList.
- XML sitemap — a map for the crawlers showing every important page.
- Robots.txt — instructions on which parts of the site should be crawled.
- HTTPS/SSL — a mandatory requirement since 2018.
- Canonical tags — to avoid duplicate content.
You can read more about technical optimisation and how speed affects SEO in our complete guide to website speed.
Off-page SEO — authority from the outside world
Off-page SEO covers everything outside your own website that influences rankings. The main factor here is backlinks — links from other sites pointing to yours. Google treats them as "recommendations". One link from a quality, authoritative site (a .bg news outlet or an industry blog, for example) is worth more than 100 links from dubious directories.
Other off-page factors include: brand mentions (even without a link), social signals, Google Business Profile optimisation and online reviews.
Core Web Vitals — Google's new currency
In 2021 Google introduced Core Web Vitals as an official ranking factor. These are three metrics that measure the real user experience:
- LCP (Largest Contentful Paint) — how long the largest element takes to load. Target: under 2.5 seconds.
- INP (Interaction to Next Paint) — responsiveness to interaction. Target: under 200ms.
- CLS (Cumulative Layout Shift) — visual stability. Target: under 0.1.
Sites that fail these tests are systematically ranked lower, no matter how good their content is.
Local SEO — essential for any business with a location
If your business has a physical presence — a restaurant, a garage, a shop, a practice, a clinic — local SEO is your single most important investment. 46% of Google searches have local intent ("dentist Sofia", "hairdresser Plovdiv centre"). For those searches Google shows a dedicated "Local Pack" with 3 businesses above the organic results.
Local SEO requires an optimised Google Business Profile, consistent NAP data (Name, Address, Phone) across every directory, local keywords on the website and active review management.
The most common SEO mistakes
- Keyword stuffing — cramming in keywords, something Google has penalised since 2012.
- Thin content — pages of 100–200 words with no real value.
- Duplicate content — the same text repeated across several pages.
- Broken links (404) — they hurt UX and waste link equity.
- Ignoring the mobile version — fatal in 2026.
- No HTTPS — an instant red flag from Google.
- Buying low-quality links — this leads to manual penalties.
How long does SEO take to deliver results?
Realistically, SEO is a long-term investment. The first results usually appear after 3–4 months, visible keyword rankings after 6 months, and meaningful organic traffic after 9–12 months. It depends on how competitive your niche is, the starting condition of the website and how consistently the work is done.
Anyone who promises you "page one in 30 days" or sells you a guaranteed ranking is lying. Good SEO takes time, but the results last for years.
Conclusion — SEO isn't optional, it's a requirement
In 2026 SEO is no longer a "bonus" for advanced businesses — it is the foundation without which a website makes no sense. The good news is that SEO traffic is free, high-quality and sustainable. Once your positions are built, they work for you for months and years, without you paying for every single click.
If you want to know where your website stands right now, take a look at our SEO services or drop us a line for a free audit. We'll be honest with you about what is worth fighting for — and what isn't.
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