What is SEO ? A plain English guide

Search engine optimisation is often described as if it were a trick. It is not. It is the ordinary work of building a website that answers what people search for, on a site that loads properly and that other credible sites reference. This guide covers the whole picture, in the order it usually matters.

How Google decides what to show

Three things happen before your page can rank. Google has to crawl it, meaning find and read it. It has to index it, meaning decide it is worth storing. Then it has to rank it, meaning judge it against every other page competing for the same search.

Ranking is a judgement about two things: relevance, meaning does this page answer the question, and trust, meaning is this a source worth showing. Content and keywords address relevance. Links, reviews and brand recognition address trust. Everything in SEO is one of those two, or is fixing something preventing the first two steps.

The four parts of SEO

1. Technical. Making the site fast, crawlable and correctly structured, so Google can read it and people do not leave. See technical SEO explained.
2. Content and on page. Having a page for each thing people search, written properly and structured clearly. See on page SEO basics.
3. Links and authority. Earning references from other credible sites. See link building explained.
4. Local. For any business serving a place, your Google Business Profile, reviews and local relevance. See the local SEO guide.

A campaign that only does one of these rarely works. A campaign that does the fourth one properly, for a local business, often works on its own.

Google ranks pages, not websites

This is the most useful thing a non specialist can understand. Your homepage cannot rank for everything. If you offer six services, you need six pages, each one built around what people actually type when they want that service. This is why keyword research comes before writing, not after.

It is also why directories like this one exist as separate pages per sector and per place: someone searching SEO for plumbers in Bristol wants a different page to someone searching technical SEO Bristol, even though both are about the same industry.

Search intent, and why it decides everything

Every search carries an intent. Someone typing "how much does a new boiler cost" wants information. Someone typing "boiler installation Bristol" wants to buy. Google knows the difference and shows completely different results for each. Aim a sales page at an information search and it will not rank, however well written it is.

The practical test is free: search the term yourself and look at what already ranks. If the first page is all guides, you need a guide. If it is all service pages, you need a service page. If it is a map pack, you need local SEO rather than a blog.

How long it takes and why

SEO compounds. Nothing much happens for the first two or three months, then the pages published early start to earn, and each new page arrives on a site Google trusts a little more. That shape is why it is poor value for a business that needs customers next week and excellent value for one that will still be trading in three years. How long SEO takes to work covers the realistic timeline, and SEO vs PPC covers what to do about the gap in the meantime.

What it costs to buy

Most UK small businesses pay £500 to £2,500 a month, and the number depends on competition, the state of the site and how much content is needed. Our SEO pricing guide sets out the ranges in full, and if you are ready to talk to somebody, you can compare SEO agencies in Bristol or request quotes and judge the answers against these questions.