What is SEO? A Beginner's Guide to Search Engine Optimisation

SEO — Search Engine Optimisation — is the practice of improving your website so it appears higher in search results on Google and other search engines. Higher rankings mean more visitors, and more visitors means more business. It sounds simple, but there's a lot going on under the hood.

What is SEO — the simple definition

SEO stands for Search Engine Optimisation. It's the process of making changes to your website — and building authority for it — so that search engines like Google rank it higher for relevant searches.

When someone types "best running shoes" into Google, they see a list of results. The websites at the top of that list have (usually) done good SEO. They've convinced Google that their page is the most relevant, trustworthy, and useful result for that search.

Unlike paid advertising (where you pay to appear at the top), SEO is about earning those rankings organically. It takes more time, but the traffic you get is free and sustainable.

How search engines work

To understand SEO, you need to understand what search engines actually do. Google follows three main steps:

1. Crawling

Google uses automated programs called "crawlers" or "spiders" that browse the web, following links from page to page. When a crawler finds your page, it reads the content and sends that information back to Google's servers.

2. Indexing

Once crawled, Google stores information about your page in its massive database — the index. If your page isn't in the index, it won't appear in search results at all. You can check if your pages are indexed using Google Search Console.

3. Ranking

When someone searches for something, Google uses over 200 ranking factors to decide which pages to show and in what order. These factors include the relevance of your content, the quality of your links, your page speed, and much more.

The three types of SEO

SEO is typically divided into three main categories, and a strong strategy covers all three.

On-page SEO explained

On-page SEO refers to everything you control on your own website pages. This includes:

• Title tags — the clickable headline that appears in search results. Every page needs a unique, keyword-rich title tag.
• Meta descriptions — the short description below the title in search results. While not a direct ranking factor, a compelling meta description improves click-through rates.
• Headings (H1, H2, H3) — help structure your content and signal what your page is about.
• Content quality — Google rewards pages that genuinely answer searchers' questions better than the competition.
• Keyword usage — using your target keywords naturally throughout your content, including in headings and the first paragraph.
• Internal links — linking between your own pages helps Google understand your site structure and spreads "link equity" across your pages.
• Image alt text — describes images for both search engines and accessibility purposes.
• URL structure — clean, descriptive URLs (like /what-is-seo rather than /page?id=123) are easier for search engines to understand.

Off-page SEO explained

Off-page SEO covers things that happen outside your website that still affect your rankings. The most important is link building.

When other websites link to your pages, Google sees this as a vote of confidence. A link from a reputable website (like a major newspaper or a respected industry blog) carries more weight than a link from a small, unknown site.

Other off-page factors include:

• Brand mentions — even unlinked mentions of your brand signal authority.
• Social signals — while debated, social shares can indirectly boost SEO by driving traffic and visibility.
• Reviews and citations — especially important for local SEO.

Technical SEO explained

Technical SEO ensures that search engines can find, crawl, and index your site without obstacles. Key areas include:

• Page speed — Google uses Core Web Vitals as ranking signals. Slow pages lose rankings and users.
• Mobile-friendliness — Google uses mobile-first indexing, meaning it primarily uses the mobile version of your site for ranking.
• HTTPS / SSL — having a secure connection is a confirmed ranking factor and builds user trust.
• XML sitemap — helps Google discover all your pages more efficiently.
• Robots.txt — controls which parts of your site crawlers can access.
• Structured data / Schema — adds context for search engines and can unlock rich results (star ratings, FAQs, etc.).
• Canonical tags — prevent duplicate content issues by telling Google which version of a page is the primary one.

Why SEO matters for your business

Organic search is typically the largest source of traffic for most websites. Consider these facts:

• The first result on Google gets approximately 28% of all clicks.
• 75% of users never scroll past the first page of results.
• SEO-driven traffic converts better than most other channels because users are actively searching for what you offer.
• Unlike paid ads, good SEO keeps delivering traffic for months or years without ongoing spend.

For a local business, ranking #1 for "plumber in Manchester" or "solicitor in Bristol" can mean a constant stream of high-intent customers. For a blog or e-commerce site, organic search is often the difference between a thriving business and one that struggles to get noticed.

How long does SEO take?

This is one of the most common questions beginners ask. The honest answer: it depends, but don't expect overnight results.

For a brand new website with no existing authority, it typically takes 6–12 months to start seeing meaningful results for competitive keywords. However, targeting less competitive, long-tail keywords can show results much faster — sometimes within weeks.

For an established website with good domain authority, improvements can show up in 1–3 months after changes are made.

The key is consistency. SEO is not a one-time task — it's an ongoing commitment to improving your site and building authority over time.

How to get started with SEO

If you're new to SEO, the best place to start is with an audit of your current website. You need to know what's working, what's missing, and what needs fixing before you can build an effective strategy.

Key first steps:

1. Run a free SEO check on your site to identify quick wins and issues to fix.
2. Set up Google Search Console to see which queries bring visitors to your site.
3. Research keywords — find out what your target audience actually searches for.
4. Optimise your title tags and meta descriptions for every page.
5. Create genuinely useful content that answers your audience's questions.
6. Fix any technical issues (slow load times, broken links, missing alt text).
7. Start building links through content marketing, PR, and partnerships.

Want to dive deeper? Read our guides on how to check your website's SEO, the complete SEO checklist for 2025, and our guide to meta tags.