SEO Glossary: All Terms Simply Explained

EN: Largest Contentful Paint

LCP measures how long it takes for the largest visible element on a page (e.g. a hero image or headline) to fully load. Google rates LCP as good when it is under 2.5 seconds. A slow LCP score harms both ranking and user experience.

EN: Interaction to Next Paint

INP became an official Core Web Vital in March 2024, replacing FID. It measures how quickly a page responds to user input — clicks, taps, or keyboard presses. A good INP value is under 200 milliseconds.

EN: Cumulative Layout Shift

CLS measures how much the layout of a page shifts unexpectedly during loading — for example when a banner loads late and pushes text downward. Google rates a CLS score below 0.1 as good. High CLS frustrates users and degrades rankings.

EN: Time to First Byte

TTFB is the time between the browser sending an HTTP request and receiving the first byte of data from the server. It is an early indicator of server performance and hosting quality. A good TTFB is under 800 milliseconds.

Core Web Vitals are Google's three official user experience metrics: LCP, INP, and CLS. Since 2021, they feed directly into the Page Experience ranking signal. Webmasters can measure them in Google Search Console and PageSpeed Insights.

A canonical tag (`<link rel="canonical" href="...">`) in the HTML head tells Google the preferred URL for a piece of content when the same content is accessible at multiple URLs. It prevents duplicate content issues and consolidates link equity on the canonical version.

The hreflang attribute tells search engines which language and region a page is intended for (e.g. `hreflang="en-US"`). It prevents international websites from being penalised for duplicate content and ensures users see the correct language version.

The robots.txt file sits in the root directory of a website and controls which areas search engine crawlers are allowed to crawl. Disallow rules can block sensitive areas (e.g. admin paths) from being crawled. It does not, however, replace a noindex tag for actually excluding pages from the index.

An XML sitemap is a structured list of all indexable URLs on a website that helps search engines discover and crawl pages. It is submitted in Google Search Console and typically includes priority levels and last-modified dates.

Crawl budget is the number of pages Google crawls on a website within a given time period. For large sites (thousands of pages), crawl budget matters: unnecessary or broken pages waste budget and delay the indexing of important content.

Crawl depth describes how many clicks away from the homepage a page is located. Pages buried deep in the site structure are crawled less frequently by Googlebot. Shallow site structures (maximum 3 clicks from the homepage) are considered more SEO-friendly.

Index bloat occurs when too many low-quality or irrelevant pages are present in Google's index. This reduces crawling efficiency, as Googlebot wastes budget on worthless pages. Common causes include faceted navigation, URL parameters, and auto-generated thin pages.

A noindex tag (`<meta name="robots" content="noindex">`) or HTTP header instructs Google not to include a page in its index. It is used for thank-you pages, internal search results, or staging environments. Unlike robots.txt, noindex prevents indexation but not crawling.

The `rel="nofollow"` attribute instructs Google not to follow a link or pass PageRank. Since 2019, Google treats nofollow as a hint rather than a directive. Paid links should use `rel="sponsored"` and user-generated content links `rel="ugc"`.

AMP is a Google framework for fast-loading mobile pages that heavily restricts HTML. After Core Web Vitals became a ranking factor (2021) and the AMP carousel ended (2023), AMP has lost much of its relevance. Most sites are better served by optimising Core Web Vitals directly.

Log file analysis involves examining server log files to understand Googlebot's crawling behaviour. It reveals which pages are crawled frequently or never, where crawl budget is wasted, and whether important pages are visited regularly.

Crawl errors are errors that occur when crawling pages — for example 404 (not found) or 500 (server error). They are visible in Google Search Console under Page Indexing. Frequent crawl errors can strain crawl budget and push important pages out of the index.

Schema markup is machine-readable code (usually JSON-LD) in the HTML that tells search engines exactly what a piece of content means — whether it's a recipe, a product, or an FAQ. It forms the basis for rich snippets in search results.

Rich snippets are enhanced search results that display additional information such as star ratings, prices, images, or FAQs directly in the SERPs. They appear when Google detects valid schema markup and typically increase click-through rates (CTR) significantly.

EN: Experience, Expertise, Authoritativeness, Trustworthiness

E-E-A-T stands for Experience, Expertise, Authoritativeness, and Trustworthiness. Google evaluates content using these four quality signals in its Search Quality Rater Guidelines. E-E-A-T has an enormous influence on rankings, especially for YMYL topics.

EN: Meta Title / Title Tag

The meta title (also: title tag) is the page title in the HTML head (`<title>`) and appears as the blue headline in the search result. It is one of the strongest on-page ranking factors. Ideally it contains the main keyword and is 50–60 characters long.

The meta description is the short description below the title in search results. It is not a direct ranking factor, but significantly influences click-through rate (CTR). Google recommends a length of 150–160 characters and sometimes uses it as the snippet text.

EN: Heading Tags

Heading tags structure page content hierarchically: the H1 is the main title (only once per page), H2 tags are section headings, H3 are sub-sections. Search engines use the heading hierarchy to understand the topic structure of an article.

Keyword density describes how often a keyword appears relative to the total word count of a text. Excessive repetition is called keyword stuffing and can trigger a penalty. Modern SEO prioritises natural language and semantic context over rigid density targets.

Semantic SEO optimises content not for individual keywords but for the meaning and context of a topic. It covers related terms, entities, and questions a user might have about the subject. Google rates semantically comprehensive content as more relevant and authoritative.

EN: Latent Semantic Indexing Keywords

LSI keywords (Latent Semantic Indexing) are semantically related terms and synonyms that match the context of the main keyword. They help search engines better understand the context of a text. For the keyword "SEO", LSI keywords include "search engine optimisation", "ranking", or "SERP".

EN: Content Cluster / Topic Cluster

A content cluster is a group of thematically related pieces of content connected by internal links. At the centre is a pillar page that comprehensively covers the topic, while cluster pages explore individual aspects in depth. Content clusters signal topical authority to Google.

A pillar page is the central page of a content cluster and covers a broad topic comprehensively. It links to all associated cluster pages and receives back-links from them. Pillar pages often rank for broad keywords and strengthen the overall topical authority of the domain.

Internal linking refers to links between pages on the same website. It distributes link equity (authority), helps search engines crawl the site, and guides users to related content. A well-planned internal link structure is an often underestimated but highly effective SEO lever.

Anchor text is the clickable, visible text of a hyperlink. Search engines use it as a context signal to understand what the linked page is about. Good anchor texts are descriptive and keyword-relevant, while generic texts like "click here" carry little SEO value.

EN: Alt Text / Alternative Text

Alt text is a text description stored in an image's HTML attribute `alt="..."`. It serves accessibility purposes (screen readers), helps search engines understand images, and enables ranking in Google Image Search. Good alt text describes the image precisely and optionally includes the keyword.

Thin content refers to pages with little or no real value for users — e.g. very short texts, automatically generated pages without quality, or heavily duplicated content. Google has penalised thin content since the Panda update and systematically downgrades such pages.

Duplicate content refers to identical or near-identical content accessible at multiple URLs — internally (on the same website) or externally (across different websites). Internal duplicate content can be resolved with canonical tags. External duplicate content can lead to ranking dilution.

The HTML `<title>` element defines the page title displayed in the browser tab and as the blue headline in search results. It is one of the most important on-page ranking factors. Ideal length: 50–60 characters with the main keyword as close to the beginning as possible.

The H1 tag is the main heading of a page and should contain the primary keyword. Each page should have exactly one H1 tag. It signals to both Google and users what the central topic of the page is, and is the most important heading ranking factor after the title tag.

Keyword stuffing refers to the excessive and unnatural repetition of keywords in a text in an attempt to manipulate rankings. Google penalises this practice algorithmically. Modern SEO focuses on semantically rich text with natural language rather than rigid keyword density targets.

EN: TF-IDF (Term Frequency–Inverse Document Frequency)

TF-IDF (Term Frequency–Inverse Document Frequency) is a statistical measure of how relevant a term is within a document compared to a collection of documents. It helps identify which terms are most characteristic of a given topic. Many SEO tools use TF-IDF analysis for content optimisation recommendations.

Cornerstone content refers to the most important, most comprehensive articles on a website — the core content for its central topics. These pages receive priority internal linking and are meant to rank for the most important keywords. The concept was popularised by Yoast SEO and is similar to the pillar page model.

Above the fold refers to the area of a webpage visible without scrolling — named after the newspaper practice of placing the most important content above the physical fold. This area is especially important for CTAs, first impressions, and user guidance. Google also evaluates ad density above the fold.

EN: Backlinks / Inbound Links

Backlinks are external links from other websites pointing to your own site. They are considered the most important off-page ranking signal: many high-quality backlinks signal to Google that a page is trustworthy and relevant. Quality of the linking domain matters far more than sheer quantity.

Domain Authority (DA by Moz) and Domain Rating (DR by Ahrefs) are proprietary metrics from SEO tools that rate the link authority of a domain on a scale of 0–100. They are not official Google values, but useful comparative metrics for link building and competitive analysis.

Link building is the deliberate process of acquiring backlinks from external websites. Strategies range from content marketing (content that attracts natural links) to guest posting and digital PR. High-quality links from relevant, authoritative domains have the greatest impact on rankings.

PageRank is the original algorithm by Larry Page and Sergey Brin that evaluates the relevance of a page based on the quantity and quality of inbound links. Google no longer publishes a public PageRank score, but continues to use similar link-authority signals internally as a ranking factor.

Dofollow links pass PageRank and SEO authority to the linked page. Nofollow links (with `rel="nofollow"`) officially do not — though Google may treat them as hints rather than directives. Sponsored links should be marked with `rel="sponsored"` and user-generated content links with `rel="ugc"`.

EN: Guest Posting / Guest Blogging

Guest posting involves writing articles for external websites in exchange for a backlink in the author bio or body of the article. It is a proven link building strategy that also increases reach and authority in a given topic area. Google cautions against excessive guest posting done purely for links.

Link juice is an informal SEO term for the authority or PageRank value transferred from one page to another via a link. Dofollow links pass link juice; nofollow links officially do not. Distributing link juice strategically through internal linking is an important SEO lever.

Toxic links are backlinks from low-quality, spammy, or thematically irrelevant websites that can negatively impact rankings. They often result from black-hat SEO practices or unwanted link schemes. The Google Disavow Tool allows webmasters to instruct Google to ignore such links.

The Google Disavow Tool allows webmasters to instruct Google to ignore certain backlinks when evaluating their website. It should only be used when there are clear signs of a manual penalty or a large number of toxic links. The file is uploaded as a TXT list in Google Search Console.

The Skyscraper Technique is a link building strategy by Brian Dean (Backlinko): identify well-linked top content on a topic, create a significantly better version, then contact the websites linking to the original. The goal is to win backlinks through superior content.

Broken link building is a strategy where broken links on other websites are identified and used as an opportunity to offer your own content as a replacement. It benefits the webmaster (broken links get fixed) and the SEO practitioner (a backlink is gained).

EN: AI Overviews / Search Generative Experience

AI Overviews (formerly Search Generative Experience) are AI-generated summaries that Google has displayed above organic search results since 2024. They cite sources and can significantly reduce organic traffic (zero-click effect). Websites with clear, structured definitions are cited as sources more frequently.

EN: Generative Engine Optimization

GEO (Generative Engine Optimization) refers to optimising content to be cited in AI-powered search results — such as Google AI Overviews, Perplexity, or ChatGPT Search. Clear definitions, structured data, E-E-A-T signals, and a llms.txt file play a decisive role.

EN: Large Language Model

A Large Language Model (LLM) is an AI language model trained on vast amounts of text that can understand and generate human language — for example GPT-4, Claude, or Gemini. LLMs form the technological foundation for AI search, AI chatbots, and AI-powered content tools like AniSEO.

llms.txt is a file in the root directory of a website (analogous to robots.txt) that provides structured information about the company, products, and key content for Large Language Models. It improves how LLMs understand a website and cite it in AI responses. The format was proposed by fast.ai in 2024.

The Helpful Content Update is a Google algorithm update (since 2022) that favours content created primarily for humans rather than search engines. It penalises websites whose content is mainly aimed at ranking manipulation rather than delivering genuine value.

EN: Your Money or Your Life

YMYL describes topics that can have significant consequences for health, finances, safety, or societal participation — e.g. medical guides, financial advice, or legal information. Google holds YMYL pages to particularly strict E-E-A-T standards and evaluates them with greater scrutiny.

In a zero-click search, the query is answered directly on the Google results page — via featured snippets, knowledge panels, or AI overviews — without the user clicking through to a website. Studies show that more than 50% of all Google searches now end without a click.

A featured snippet is a highlighted answer box that Google displays directly above organic search results, briefly summarising the information sought. It is also called "Position 0" because it appears above the first organic result. Clear, concise answers in the content help earn featured snippets.

People Also Ask (PAA) is a box in Google search results that shows frequently asked follow-up questions related to the search term. Each question can be expanded to reveal a short answer from a website. PAA visibility is a strong signal of user relevance and is boosted by FAQ schema markup.

The Knowledge Graph is Google's semantic knowledge database containing billions of entities (people, places, companies, concepts) and their relationships. It allows Google to understand meaning rather than just matching characters. Businesses and brands can earn their own Knowledge Graph entry, increasing visibility and trust.

EN: Search Volume / Monthly Search Volume

Search volume indicates how often a particular keyword is entered in a search engine on average per month. It is a core metric in keyword prioritisation: high search volumes offer greater traffic potential but are often more competitive.

EN: Keyword Difficulty

Keyword Difficulty (KD) is a metric from SEO tools (e.g. Ahrefs, Semrush) that indicates on a scale of 0–100 how hard it is to rank organically for a keyword. It is based primarily on the strength of the backlink profiles of currently ranking pages. For new websites, targeting keywords with KD below 30 is advisable.

Long-tail keywords are specific, multi-word search queries with lower search volume but significantly less competition and often higher conversion intent (e.g. "SEO agency for small businesses London"). They account for the vast majority of all searches and are an important entry strategy for new websites.

EN: Short-Tail Keywords / Head Terms

Short-tail keywords (also: head terms) are short, generic queries of one or two words with very high search volume (e.g. "SEO" or "marketing"). They are extremely competitive and require high domain authority to rank for. Traffic is often less targeted than with long-tail keywords.

EN: Search Intent / User Intent

Search intent is the underlying purpose behind a search query. Google distinguishes four types: informational (seeking information), navigational (looking for a specific site), transactional (intent to buy), and commercial (comparing products). Content that doesn't match search intent will not rank well — regardless of keyword optimisation.

EN: Search Engine Results Page

SERP stands for Search Engine Results Page — the results page of a search engine after a query. A SERP contains organic results, paid ads (Google Ads), and various SERP features such as featured snippets, shopping boxes, or People Also Ask. SERP analysis is the first step of any keyword strategy.

EN: Click-Through Rate

CTR is the ratio of clicks to impressions in search results, expressed as a percentage. A high CTR signals to Google that a search result is attractive and relevant to users. Meta title and meta description are the most important levers for improving the CTR of organic results.

Impressions refer to the number of times a URL was shown in search results — regardless of whether it was clicked. They are an important visibility KPI in Google Search Console. Many impressions combined with a low CTR indicate optimisation potential for the title and description.

Seed keywords are the starting terms for a keyword research process — broad, general terms related to a topic from which more specific keywords are derived using keyword tools. A seed keyword for a law firm might be 'lawyer' or 'legal advice'.

Keyword clustering is the grouping of thematically related keywords into clusters, each assigned to a specific page or article. It prevents keyword cannibalization, improves content structure, and enables a single page to rank for multiple related keywords.

Keyword cannibalization occurs when multiple pages on the same website rank for the same keyword, competing with each other. Google distributes authority across multiple pages instead of concentrating it on one strong page. The solution is typically consolidating pages or noindexing weaker variants.

Branded keywords are search queries containing the brand name (e.g. "AniSEO reviews" or "AniSEO pricing"). They typically have high CTR and conversion rates since users are already familiar with the brand. Branded traffic in Google Search Console is a key indicator of brand awareness.

Non-branded keywords are generic search queries without brand reference (e.g. "SEO tool for WordPress"). They are the primary source of new organic traffic and require a deliberate keyword and content strategy. The share of non-branded traffic shows how strong the generic SEO visibility is.

Negative keywords are search terms for which an ad or page is deliberately not shown. In Google Ads, they prevent irrelevant clicks and save budget. In organic SEO the concept is less directly applicable, but relevant for content targeting decisions.

Question keywords are search queries phrased as questions (Who, What, How, Why, When). They often have informational search intent and frequently form the basis for Featured Snippets and People Also Ask boxes. Tools like Answer the Public or AlsoAsked help identify relevant questions.

Evergreen content is timeless content that continuously generates traffic and doesn't become outdated — in contrast to news articles or seasonal content. Examples include how-to guides, definitions, and best-practice articles. Evergreen content offers the highest return on investment in content marketing.

Content decay refers to the gradual decline in organic traffic for older content that hasn't been updated. Causes include outdated information, new competitors, or changed search intent. Regular content audits help identify content decay early and take corrective action.

A content audit is a systematic review of all website content for SEO performance, freshness, quality, and strategic relevance. Pages are categorised as: update, consolidate, noindex, or delete. Content audits form the foundation of any sustainable content strategy.

A content gap refers to topics or keywords that competitors rank for but your website has no content for yet. Content gap analysis is a core component of keyword research and helps identify untapped traffic opportunities. Tools like Ahrefs and Semrush offer dedicated content gap features.

EN: Hub-and-Spoke Content Model

The hub-and-spoke model is a content strategy with a central hub article (covering the main topic at a high level) and specialised spoke articles (exploring individual aspects in depth). It resembles the pillar-cluster model and strengthens the topical authority of a domain.

EN: User Generated Content

User Generated Content (UGC) is content created by users — e.g. comments, reviews, forum posts, or social media contributions. UGC can increase a website's content volume and relevance, but requires moderation. Links in UGC should be marked with `rel="ugc"`.

Average position in Google Search Console shows the mean ranking position of a URL or keyword over a given period. A position of 1 means first place in search results. Important: this metric is an average and conceals variation across individual queries.

Bounce rate is the percentage of users who leave a website after visiting only a single page without interacting. In Google Analytics 4, the classic bounce rate has been replaced by the engagement rate. A high bounce rate can indicate a lack of content relevance.

Dwell time is the amount of time a user spends on a page before returning to the search results. It is considered an indirect user signal: long dwell times suggest relevant, valuable content. While Google has not officially confirmed dwell time as a ranking factor, it is an important indicator of user satisfaction.

EN: Google Search Console

Google Search Console is a free Google tool for webmasters to monitor rankings, impressions, CTR, crawling status, and indexation issues. It shows manual actions (penalties), Core Web Vitals data, and security issues. GSC is the most important free SEO analysis tool available.

EN: Google Analytics 4

Google Analytics 4 (GA4) is Google's current analytics platform, which replaced Universal Analytics in July 2023. It uses an event-based data model rather than session-based measurement. GA4 offers improved conversion tracking capabilities and is designed for more privacy-friendly tracking.

Share of Voice (SoV) is a website's market share of visible rankings for a defined group of keywords. It measures how dominant a domain is in organic search results compared to competitors. A rising SoV is a strong indicator of growing SEO strength.

Google Business Profile (formerly Google My Business) is a free Google service that allows local businesses to manage their presence in Google Maps and local search results. A fully completed profile with reviews, opening hours, and photos is the foundation of every local SEO strategy.

NAP stands for Name, Address, Phone Number — the three most important business data points for local SEO. Consistent NAP representation across all online platforms (website, Google Business Profile, directories) is an important ranking signal for local search queries.

The Local Pack (also: Map Pack) is the map with three local business results that Google displays above organic results for searches with local intent (e.g. 'dentist London'). Placement in the Local Pack depends on relevance, distance, and prominence of the Google Business Profile.

Citations are mentions of a business's name, address, and phone number (NAP) on external websites, directories, and platforms — even without a direct link. They are an important ranking signal for local SEO. Consistency of NAP data across all citations is critical.

Product schema is JSON-LD markup for product pages that enables Google to display price, availability, reviews, and other product details directly in search results (rich snippets). It significantly increases the visibility and CTR of e-commerce pages.

Faceted navigation refers to filter and sorting functions in e-commerce shops (e.g. by colour, size, price). Without correct technical implementation (canonical tags, noindex, parameter handling), they generate large numbers of thin pages and cause index bloat. One of the most common technical SEO challenges in e-commerce.

A shopping feed (product data feed) is a structured file containing product information such as title, description, price, image, and availability for Google Shopping. It is uploaded via Google Merchant Center and forms the basis for shopping ads in Google search results.