SEO Glossary
Your comprehensive guide to SEO and digital marketing terminology. Whether you're new to digital marketing or need a quick refresher, this glossary covers the essential terms you need to know.
A
Alt Text
A short, descriptive attribute added to an image’s HTML tag that tells search engines and screen readers what the image depicts. Well-written alt text improves accessibility and helps images rank in Google Image Search.
Anchor Text
The visible, clickable text within a hyperlink. Search engines use anchor text to understand the context and relevance of the linked page, making it an important factor in both on-page and off-page SEO.
B
Backlink
A link from one website to another, also known as an inbound link. Backlinks from authoritative, relevant sites signal trust to search engines and are one of the strongest ranking factors in Google’s algorithm.
Bounce Rate
The percentage of visitors who leave a website after viewing only one page without taking any further action. A high bounce rate may indicate that the landing page content or user experience is not meeting visitor expectations.
Breadcrumbs
A navigational aid that displays the user’s path from the homepage to the current page, typically shown as a horizontal trail of links. Breadcrumbs improve site usability and can appear as rich results in search engine listings.
C
Canonical URL
An HTML element (rel="canonical") that tells search engines which version of a page is the preferred or authoritative one. Canonical tags prevent duplicate content issues when the same content is accessible via multiple URLs.
Click-Through Rate (CTR)
The ratio of users who click on a specific link compared to the total number of users who view it, expressed as a percentage. In SEO, CTR measures how effectively your title tags and meta descriptions entice searchers to visit your page.
Content Marketing
A strategic approach focused on creating and distributing valuable, relevant content to attract and retain a clearly defined audience. Effective content marketing builds brand authority, earns natural backlinks, and drives organic traffic over time.
Conversion Rate
The percentage of website visitors who complete a desired action, such as making a purchase, filling out a form, or subscribing to a newsletter. Improving conversion rates is often more cost-effective than increasing traffic volume.
Core Web Vitals
A set of specific metrics defined by Google that measure real-world user experience on a web page, including loading performance (LCP), interactivity (INP), and visual stability (CLS). These metrics are confirmed ranking signals in Google’s algorithm.
Crawling
The process by which search engine bots (such as Googlebot) systematically browse the web, discovering new and updated pages by following links. A page must be crawled before it can be indexed and appear in search results.
D
Domain Authority
A search engine ranking score developed by Moz that predicts how likely a website is to rank in search engine results. While not a metric used by Google directly, it serves as a useful benchmark for comparing the relative strength of different domains.
Duplicate Content
Substantially similar or identical content that appears at more than one URL on the web. Duplicate content can confuse search engines about which version to index and rank, potentially diluting ranking signals across the duplicate pages.
E
E-E-A-T
Experience, Expertise, Authoritativeness, Trustworthiness - a framework used by Google’s Search Quality Raters to evaluate content quality. E-E-A-T is especially critical for YMYL topics, where content accuracy can directly affect a reader’s health, finances, or safety.
F
Featured Snippet
A special search result that appears at the top of Google’s organic results (often called “position zero”), displaying a concise answer extracted from a web page. Featured snippets can take the form of paragraphs, lists, tables, or videos.
G
Google Business Profile
A free tool from Google that allows businesses to manage their online presence across Google Search and Maps. Optimising your Google Business Profile is essential for local SEO, helping you appear in the local pack and attract nearby customers.
Google Search Console
A free service provided by Google that helps website owners monitor, maintain, and troubleshoot their site’s presence in search results. It provides data on search queries, indexing status, crawl errors, and Core Web Vitals performance.
H
Hreflang
An HTML attribute used to specify the language and geographical targeting of a web page. Hreflang tags help search engines serve the correct language or regional version of your content to users in different countries.
HTTP Status Codes
Three-digit responses returned by a server when a browser requests a page. Common codes include 200 (OK), 301 (permanently redirected), 404 (not found), and 500 (server error) - each carrying different implications for SEO and user experience.
I
Impressions
The number of times a URL from your site appears in search results as seen by a user. Impressions are counted regardless of whether the listing was clicked, making them a useful metric for measuring search visibility and brand awareness.
Indexing
The process by which search engines store and organise the content they have crawled so it can be retrieved and displayed in search results. If a page is not indexed, it will not appear for any search queries, regardless of its quality.
Internal Linking
The practice of linking one page of a website to another page on the same website. A strong internal linking structure helps search engines discover content, distributes page authority throughout the site, and improves user navigation.
K
Keyword Density
The percentage of times a target keyword appears on a page relative to the total word count. While there is no ideal keyword density, overusing keywords (keyword stuffing) can trigger search engine penalties and harm readability.
Keyword Research
The process of identifying and analysing the search terms that people enter into search engines to find information, products, or services. Thorough keyword research forms the foundation of any effective SEO strategy by revealing user intent and opportunity.
L
Link Building
The practice of acquiring hyperlinks from other websites to your own, with the goal of improving search engine rankings. Effective link building focuses on earning high-quality, relevant links through content creation, outreach, and digital PR.
Local SEO
A branch of search engine optimisation focused on improving visibility for businesses that serve customers in a specific geographic area. Local SEO tactics include optimising your Google Business Profile, earning local citations, and targeting location-based keywords.
Long-Tail Keywords
Longer, more specific keyword phrases that typically have lower search volume but higher conversion rates. Long-tail keywords are easier to rank for and better reflect the precise intent of searchers further along in the buying journey.
M
Meta Description
An HTML element that provides a brief summary of a page’s content, typically displayed beneath the title in search engine results. While not a direct ranking factor, a compelling meta description can significantly improve click-through rates.
Meta Title
Also known as the title tag, the meta title is the HTML element that defines the title of a web page and appears as the clickable headline in search results. It is one of the most important on-page SEO elements for both rankings and CTR.
N
Nofollow
A link attribute (rel="nofollow") that tells search engines not to pass ranking credit (link equity) to the linked page. Nofollow links are commonly used for sponsored content, user-generated links, and untrusted sources.
O
Organic Traffic
Visitors who arrive at your website through unpaid search engine results rather than through paid advertisements. Organic traffic is generally considered the most sustainable and cost-effective source of website visitors over the long term.
P
Page Speed
A measurement of how quickly the content on a web page loads. Page speed is a confirmed Google ranking factor and directly impacts user experience - slower pages tend to have higher bounce rates and lower conversion rates.
PPC (Pay-Per-Click)
An online advertising model where advertisers pay a fee each time one of their ads is clicked. PPC campaigns, such as Google Ads, offer immediate visibility in search results and are often used alongside SEO for a comprehensive search strategy.
R
Robots.txt
A text file placed in the root directory of a website that instructs search engine crawlers which pages or sections they are allowed or disallowed from crawling. It is a key tool for managing crawl budget and controlling indexation.
Rich Snippet
An enhanced search result that displays additional information beyond the standard title, URL, and meta description, such as star ratings, prices, or recipe details. Rich snippets are generated from structured data (schema markup) on your page.
S
Schema Markup
A standardised vocabulary of structured data (from schema.org) that you can add to your HTML to help search engines understand your content more precisely. Schema markup can enable rich snippets, knowledge panels, and other enhanced search features.
SERP
Search Engine Results Page - the page displayed by a search engine in response to a user’s query, containing organic results, paid ads, featured snippets, and other SERP features. Understanding SERP layout helps SEO professionals optimise for maximum visibility.
Sitemap
An XML file that lists all the important pages on your website, helping search engines discover and crawl your content more efficiently. Submitting a sitemap via Google Search Console is a best practice for ensuring comprehensive indexation.
T
Technical SEO
The process of optimising a website’s infrastructure to make it easier for search engines to crawl, index, and render its content. Technical SEO covers areas such as site speed, mobile-friendliness, structured data, XML sitemaps, and secure connections (HTTPS).
Title Tag
An HTML element that specifies the title of a web page, displayed in browser tabs, search results, and social media shares. Title tags should be concise (under 60 characters), include primary keywords, and accurately describe the page’s content.
U
URL Structure
The format and organisation of a web page’s address. Clean, descriptive URLs that include relevant keywords and follow a logical hierarchy improve both user experience and search engine understanding of your site’s content.
User Experience (UX)
The overall experience a visitor has when interacting with a website, encompassing factors like page speed, navigation, design, and content quality. Google increasingly uses UX signals - including Core Web Vitals - as ranking factors in its algorithm.
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