SEO Glossary and Quiz

SEO can seem complicated when the advice is full of unfamiliar terms. This glossary explains the language in plain English, helping you understand how search engines find your pages and how customers discover your business.

Use it to look up a term, refresh your knowledge or get more from a conversation about your website. Then try the quiz to check what you’ve learned.

Common SEO Terms Explained

SEO comes with plenty of terminology. This glossary explains some of the most common SEO terms in straightforward language, from crawling and indexing to internal linking, schema and technical SEO.

Alt Text (Alternative Text)

Alt text is a written description associated with an image that helps people using screen readers understand its content or purpose. It can also provide search engines with useful context about an image. Informative images should have meaningful alt text, while purely decorative images generally don't need a descriptive alternative.

Backlinks

Backlinks are links from other websites to pages on your website. Relevant links from reputable sources can help search engines discover your content and provide signals about its authority and credibility. Backlinks can also generate referral traffic by introducing your business to audiences on other websites.

Bounce Rate

Bounce rate is the percentage of sessions that are not considered engaged sessions in Google Analytics 4. A high or low bounce rate is not automatically good or bad — it needs to be interpreted alongside the purpose of the page, user behaviour and conversions. Bounce rate itself should not be treated as a direct Google ranking factor.

Canonical Tag

A canonical tag identifies the preferred version of a webpage when identical or very similar content is available at multiple URLs. It helps search engines understand which URL should generally be treated as the primary version and can help consolidate ranking signals. Canonical tags are a strong signal rather than an absolute directive, so search engines may choose a different canonical when other signals suggest another URL is more appropriate.

Crawling

Crawling is the process search engines use to discover and revisit webpages by following links and other signals such as XML sitemaps. Search engine crawlers retrieve information from pages so it can be processed and considered for indexing. A page being crawled does not automatically mean it will be indexed or appear in search results.

CTR (Click-Through Rate)

Click-through rate (CTR) is the percentage of people who click a search result, advert or link after seeing it. In organic search, CTR can help indicate how effectively a search listing attracts clicks, but it varies considerably depending on search intent, ranking position and the type of results displayed. It should therefore be interpreted alongside impressions, rankings, traffic and conversions rather than in isolation.

Domain Authority (DA)

Domain Authority is a third-party metric developed by Moz that estimates a website’s relative ability to rank in search results, based largely on its link profile. It can be useful when comparing websites or assessing link opportunities, but it is not a Google metric and Google does not use Domain Authority as a ranking factor.

Duplicate Content

Duplicate content is identical or substantially similar content that appears on more than one URL, either within the same website or across different websites. It doesn't automatically result in a Google penalty, but it can make it harder for search engines to determine which version should be indexed or shown in search results. Canonical tags and clear site structure can help manage duplicate content.

Google Analytics

Google Analytics 4 (GA4) is Google’s website and app analytics platform. It helps you understand how visitors find and interact with your website and can measure important actions such as enquiries, purchases and other conversions. For SEO, GA4 helps assess the quality and behaviour of organic traffic rather than simply counting visits.

Google Search Console

Google Search Console is a free Google tool that helps website owners understand how their site performs in Google Search. It provides data on search queries, impressions, clicks, average positions and indexing, while also highlighting crawling and technical issues. It is particularly useful for identifying which pages and searches are gaining visibility and where SEO opportunities may exist.

H1 Tag

The H1 is the main heading of a webpage and usually describes its primary topic. A clear, descriptive H1 helps visitors quickly understand what the page is about and gives search engines useful context about the content. It should be written naturally for the page rather than simply used as a place to insert keywords.

Internal Linking

Internal links connect one page of your website to another. They help visitors discover related content, help search engines crawl and understand the structure of your website, and provide context about how different pages and topics relate to each other. A well-planned internal linking structure can also help distribute authority towards important service, product and information pages.

Indexing

Indexing is the process by which search engines analyse and store information about webpages they have discovered. Once a page is indexed, it becomes eligible to appear in search results, but indexing alone does not guarantee that the page will rank or be shown for a particular search. Clear site structure, useful content and internal linking can help search engines discover and understand important pages.

Keywords

Keywords are the words and phrases people use when searching for information, products or services. In SEO, understanding relevant keywords helps identify what potential customers are looking for and the language they use. Effective optimisation focuses not only on individual keywords but also on the search intent behind them and whether a page genuinely satisfies that intent.

Search Intent

Search intent describes what a person is trying to achieve when they perform a search. They may be looking for information, comparing options, trying to find a particular website or preparing to make a purchase or enquiry. Understanding search intent helps ensure that a webpage provides the type of content and next step the user is actually looking for, rather than simply targeting the words used in the search.

Keyword Research

Keyword research is the process of identifying and analysing the searches people use when looking for information, products or services. It considers factors such as search volume, competition, search intent and relevance to the business. Good keyword research helps determine which topics and searches are worth targeting and which pages are best suited to satisfy them.

Landing Page

A landing page is the page a visitor arrives on after clicking a search result, advert, email or other link. An effective landing page should closely match the visitor’s intent and make the next action clear. In SEO and paid advertising, sending visitors to the most relevant service, product or information page can improve both user experience and the likelihood of conversion.

Local SEO

Local SEO focuses on improving a business’s visibility for searches connected to a particular location or service area. It can include optimising a Google Business Profile, maintaining accurate business information, building relevant local citations and creating location-focused website content. It is particularly important for businesses that rely on customers within specific towns, counties or regions.

Meta Description

A meta description is a short summary written to describe the content of a webpage. Search engines may use it as the descriptive snippet beneath a page title in search results, although they can also generate their own snippet based on the search query. A clear and relevant meta description can help users understand what a page offers and encourage qualified clicks.

NAP (Name, Address, Phone Number)

NAP refers to a business’s Name, Address and Phone Number. Keeping this information accurate and consistent across your website, Google Business Profile and relevant online directories helps customers and search engines identify the business and its location. NAP consistency is particularly important when managing a business’s local search presence.

Organic Search

Organic search refers to the unpaid results shown by search engines in response to a user’s query, rather than paid advertisements. SEO aims to improve a website’s visibility within these results by making its pages relevant, useful and technically accessible. Organic search can bring ongoing traffic from people actively looking for information, products or services related to your business.

SERP (Search Engine Results Page)

A Search Engine Results Page (SERP) is the page displayed by a search engine in response to a query. Depending on the search, it can contain organic listings, paid advertisements, maps, images, videos, shopping results, featured information and AI-generated features. Understanding the different elements of a SERP helps identify where and how a business can gain visibility beyond simply achieving a traditional organic ranking.

Page Speed

Page speed describes how quickly a webpage loads and becomes usable for visitors. Good performance improves user experience, particularly on mobile devices, and can be assessed using measures such as Google’s Core Web Vitals. Page experience can contribute to search performance, but speed should not be treated as a standalone route to higher rankings — useful, relevant content and search intent remain fundamental.

Core Web Vitals

Core Web Vitals are Google metrics used to assess important aspects of a webpage’s user experience, including loading performance, responsiveness and visual stability. The current metrics are Largest Contentful Paint (LCP), Interaction to Next Paint (INP) and Cumulative Layout Shift (CLS). They form part of Google’s broader assessment of page experience, but strong Core Web Vitals alone do not guarantee higher search rankings.

Schema Markup

Schema markup is structured data added to a webpage to help search engines understand specific information about its content, such as a business, product, service, article or FAQ. Supported structured data can make pages eligible for enhanced search features, although these are not guaranteed. Schema also provides machines with clearer context about the entities and information represented on a page.

Search Engine Optimisation (SEO)

Search Engine Optimisation (SEO) is the process of improving a website’s visibility in unpaid search results. It combines technical SEO, content and on-page optimisation, internal linking, local SEO where relevant, and off-page signals to help search engines understand a website and connect its pages with relevant searches. The goal is to attract useful, qualified organic traffic that can contribute to genuine business outcomes.

Answer Engine Optimisation (AEO)

Answer Engine Optimisation (AEO) focuses on making content clear, useful and well structured so it can be understood and surfaced by search engines, AI-powered search experiences and other systems that provide direct answers to users. It builds on established SEO practices such as strong content, clear page structure, relevant entities, internal linking and structured data rather than replacing traditional SEO.

Search Engine Rankings

Search engine rankings describe where a webpage appears in search results for a particular query. Rankings can vary by search term, location, device and other contextual factors. Improving visibility for relevant searches can be valuable, but rankings should be considered alongside impressions, clicks, qualified traffic and conversions rather than treated as the sole measure of SEO success.

Search Terms (Search Queries)

Search terms, or search queries, are the actual words and phrases people enter into a search engine. Analysing these searches helps you understand customer language, needs and intent, and can reveal opportunities for new or improved content. Search queries are not always the same as the keywords a business chooses to target — they represent what users actually searched for.

Site Map

A sitemap helps search engines discover and understand the pages on a website. An XML sitemap provides search engines with a structured list of important URLs that may be available for crawling and indexing. A website can also have an HTML sitemap designed for visitors, providing another way to navigate and discover important content.

Technical SEO

Technical SEO focuses on the underlying structure and performance of a website so search engines can efficiently crawl, understand and index its content. It includes areas such as crawlability, indexing, site architecture, XML sitemaps, redirects, HTTPS, mobile usability and Core Web Vitals. Technical SEO provides the foundation that allows your content and other optimisation work to perform effectively.

Title Tag

A title tag is the HTML element that defines the title of a webpage. It helps search engines understand the page’s topic and is often used as the clickable title shown in search results, although Google may generate a different title when it considers another description more useful. A good title should clearly describe the page, reflect relevant search intent and encourage qualified users to click.

User Experience (UX)

User experience describes how easy, useful and satisfying a website is for visitors to use. It includes factors such as navigation, readability, mobile usability, accessibility, page performance and how easily users can complete important actions. Good UX supports SEO by helping visitors find and use the content they searched for, while also improving the likelihood that relevant traffic will turn into enquiries or sales.

White Hat SEO

White Hat SEO refers to optimisation practices that follow search engine guidelines and focus on creating genuine value for users. This includes improving website quality, publishing useful content, maintaining sound technical SEO and earning relevant links naturally. It avoids manipulative tactics designed primarily to influence rankings, such as keyword stuffing, link schemes or deceptive content practices.