Search engine optimization has its own language. Whether you are reading an SEO audit, following a guide, or talking with a developer, you will encounter dozens of specialized terms. This glossary defines the 50 most important SEO concepts with clear, practical explanations and links to free tools where applicable. For hands-on guides, explore our technical SEO audit, keyword research workflow, and on-page SEO checklist.
Use the links below to jump to the section you need, or read through from A to Z to fill any gaps in your SEO vocabulary.
Alt Text
Alt text (alternative text) is a written description of an image that is read by screen readers and search engine crawlers. It is set in the HTML img tag using the alt attribute. Good alt text describes what the image shows and includes relevant keywords where natural. It helps visually impaired users understand your content and helps search engines index your images. Every meaningful image should have alt text; decorative images should use an empty alt attribute.
Anchor Text
Anchor text is the clickable text in a hyperlink. It tells both users and search engines what the linked page is about. Descriptive anchor text like "free meta tags checker" is more helpful than generic text like "click here." Search engines use anchor text as a signal of the linked page topic, so using relevant keywords in your anchors can help with rankings. Over-optimizing anchor text with exact-match keywords can trigger penalties.
Backlink
A backlink is a link from another website to your site. Backlinks are one of the strongest ranking signals because they act as votes of confidence from other sites. Not all backlinks are equal: a link from a high-authority, relevant site carries more weight than one from a low-quality directory. Use a backlink checker to monitor who links to your site and identify opportunities.
Canonical Tag
A canonical tag (rel="canonical") is an HTML element that tells search engines which version of a page is the preferred one when duplicate or similar content exists at multiple URLs. It consolidates ranking signals to the canonical URL and prevents duplicate content issues. Without it, search engines may split ranking signals between duplicate pages or index the wrong version. Check canonical tags with a meta tags checker.
Click-Through Rate (CTR)
Click-through rate is the percentage of people who see your page in search results and click on it. A higher CTR means more traffic for the same ranking position. CTR is influenced by your title tag, meta description, URL, and whether rich results appear. Google Search Console shows CTR for each page and query. Improving title tags and meta descriptions is the fastest way to increase CTR.
Crawl Budget
Crawl budget is the number of pages a search engine will crawl on your site within a given time period. For small sites this is rarely an issue, but for large sites with thousands of pages, wasting crawl budget on low-value pages (tag pages, search results, duplicate content) means important pages may not get crawled often enough. Optimize your XML sitemap and robots.txt to focus crawling on high-value pages.
Domain Authority
Domain authority is a score (originally from Moz, now used generally) that predicts how likely a domain is to rank in search results. It is based on factors like the number and quality of backlinks, domain age, and content quality. Scores range from 1 to 100. Higher authority domains tend to rank more easily for competitive terms. It is a comparative metric, not an absolute ranking factor.
Dwell Time
Dwell time is the amount of time a user spends on your page after clicking through from search results before returning to the results page. Longer dwell time generally signals that the page is relevant and useful. It is related to but distinct from bounce rate. Improving content quality, adding internal links, and improving page speed can increase dwell time.
E-E-A-T
E-E-A-T stands for Experience, Expertise, Authoritativeness, and Trustworthiness. It is a framework Google uses to evaluate the quality of content, particularly for topics that affect health, finance, or safety (YMYL pages). Demonstrating real experience, subject matter expertise, authoritative sourcing, and trust signals helps content rank well. It is not a direct ranking factor but influences how quality raters evaluate results.
Featured Snippet
A featured snippet is a highlighted answer box that appears at the top of Google search results, above the first organic result. It extracts content from a webpage that directly answers the search query. Featured snippets can be paragraphs, lists, tables, or videos. To optimize for them, structure your content with clear question-and-answer formats using h2 and h3 headings.
Google Search Console
Google Search Console is a free tool from Google that shows how your site performs in search. It reports on indexing status, search queries, click-through rates, core web vitals, mobile usability, and manual actions. It is essential for every site owner. Verify your site to access the data and check it weekly for coverage issues and performance trends.
H1 Tag
The H1 tag is the main heading of a page and is the most important heading for SEO. There should be exactly one H1 per page, and it should clearly describe the page topic and include the primary keyword. The H1 is typically the same as or similar to the title tag. Search engines use the H1 as a strong signal of page topic. Use a heading structure checker to verify your H1 is correctly set.
Indexing
Indexing is the process by which search engines store and organize content from the web. When a search engine crawls your page, it adds the content to its index (like a massive library catalog). Only indexed pages can appear in search results. A page may not be indexed if it has a noindex directive, is blocked by robots.txt, has a canonical pointing elsewhere, or is considered low quality. Check your index status in Google Search Console.
Internal Link
An internal link is a link from one page on your site to another page on the same site. Internal links distribute authority across your site, help search engines discover new pages, and guide users to related content. A strong internal linking structure ensures your most important pages are linked from multiple other pages. Every new page should be reachable from at least one existing page.
Keyword Density
Keyword density is the percentage of times a keyword appears relative to the total word count on a page. Historically, SEO practitioners tried to hit specific density targets, but modern search engines use natural language processing and do not rely on keyword density. Focus on natural language and topical coverage rather than hitting a specific density number.
Keyword Stuffing
Keyword stuffing is the practice of loading a page with keywords in an unnatural way to try to manipulate rankings. It is a black-hat technique that search engines penalize. Modern search engines understand context and synonyms, so keyword stuffing is both ineffective and risky. Write for humans first, and include keywords naturally where they fit.
Largest Contentful Paint (LCP)
LCP measures how long it takes for the largest visible element on a page to load. It is one of the three Core Web Vitals metrics. A good LCP is under 2.5 seconds. Slow LCP scores are often caused by large images, slow server response times, or render-blocking resources. Use a pagespeed checker to measure your LCP.
Link Equity
Link equity (also called link juice) is the authority and value passed from one page to another through a hyperlink. DoFollow links pass link equity; NoFollow links do not (or pass less). Pages with more inbound link equity tend to rank higher. Internal linking distributes your site existing equity to the pages that need it most.
Meta Description
A meta description is an HTML attribute that provides a brief summary of a page for search engine results pages (SERPs). It does not directly affect rankings, but it influences click-through rate. A good meta description is 150-160 characters, includes the target keyword, and gives users a reason to click. Use a meta tags checker to review your current descriptions.
Meta Robots Tag
The meta robots tag is an HTML tag that tells search engines how to handle a page. Common values include index/noindex (whether to include the page in the index) and follow/nofollow (whether to follow links on the page). The tag is set in the head section of the HTML. A common mistake is accidentally leaving a noindex tag on a page after launching it to production.
NoFollow
NoFollow is a link attribute (rel="nofollow") that tells search engines not to pass link equity through a link. It was originally designed for paid links, user-generated content, and untrusted links. Google now treats NoFollow as a hint rather than a directive. Use NoFollow for links you do not want to endorse, such as affiliate links or user comments.
NoIndex
NoIndex is a directive that tells search engines not to include a page in their index. A noindexed page will not appear in search results even if it is crawlable. Common uses include internal search results, thank-you pages, and draft content. A page can be crawled but not indexed if the noindex tag is present. Verify with a meta tags checker.
Open Graph Tags
Open Graph tags are HTML meta tags that control how a page appears when shared on social media platforms like Facebook, LinkedIn, and WhatsApp. Key tags include og:title, og:description, og:image, and og:url. Proper Open Graph setup ensures your pages look professional when shared. Use a Open Graph checker to validate your tags.
Orphan Page
An orphan page is a page on your site that has no internal links pointing to it. Search engines discover pages through links, so orphan pages are hard to crawl and rarely indexed. They also do not receive any link equity from your internal linking structure. Every important page should be linked from at least one other page on your site, ideally from your navigation or a prominent content page.
Page Speed
Page speed is how quickly a page loads and becomes interactive for the user. It is a confirmed ranking factor and directly impacts user experience and conversion rates. Core Web Vitals (LCP, INP, CLS) measure specific aspects of page speed. Use a pagespeed checker to test individual pages and a bulk Core Web Vitals checker for multiple URLs.
Redirect
A redirect automatically sends users and search engines from one URL to another. The most common types are 301 (permanent redirect) and 302 (temporary redirect). 301 redirects pass the majority of link equity; 302 redirects pass less. Use 301 for permanent URL changes and 302 for temporary ones. Check redirect chains with a redirect checker.
Robots.txt
Robots.txt is a file at the root of your site that tells search engine crawlers which pages or directories they are allowed to crawl. It is a crawling directive, not an indexing directive. A page blocked by robots.txt may still be indexed if other sites link to it. Use a robots.txt checker to verify no rule is accidentally blocking important pages.
Schema Markup
Schema markup (also called structured data) is a standardized format for providing information about a page and its content to search engines. It is written in JSON-LD format and placed in the page head. Schema markup helps search engines understand your content and can unlock rich results like FAQ dropdowns, product stars, and event listings. Use a schema markup generator to create valid JSON-LD.
Search Engine Results Page (SERP)
A SERP is the page a search engine displays after a user submits a query. It contains organic results, paid ads, featured snippets, knowledge panels, image carousels, and other result types. Understanding SERP features is important for SEO because the layout affects where users click. Optimizing for featured snippets, image results, and other SERP features can increase visibility even without a number-one ranking.
Thin Content
Thin content is pages with little or no valuable information. It can be very short articles, auto-generated content, doorway pages, or pages with mostly affiliate links and no original value. Google Panda and subsequent updates penalize thin content. Aim for comprehensive, useful content that fully addresses the topic. If a page does not add value beyond what already exists on your site, consider consolidating or removing it.
Title Tag
The title tag is an HTML element that defines the title of a page. It appears in browser tabs, search results, and social shares. It is one of the strongest on-page ranking signals. A good title tag is under 60 characters, contains the primary keyword, and communicates a clear benefit. Use a meta tags checker to review your current titles and a meta title generator for new pages.
URL Slug
The URL slug is the part of the URL that identifies a specific page in readable form. For example, in example.com/seo-glossary, "seo-glossary" is the slug. A good slug is short, descriptive, and includes the target keyword. Avoid numbers, special characters, and excessive parameters in slugs. Once a page is indexed, changing the slug requires a 301 redirect from the old URL.
User Intent
User intent (also called search intent) is the reason behind a search query. It falls into four main categories: informational (looking for information), navigational (looking for a specific site), commercial (researching before a purchase), and transactional (ready to buy). Understanding the intent behind your target keywords is critical for creating content that ranks. A page optimized for informational intent will not rank for a transactional query, and vice versa.
White Hat SEO
White hat SEO refers to optimization techniques that follow search engine guidelines and focus on providing value to users. It includes creating high-quality content, earning natural backlinks, optimizing on-page elements, and improving site speed. White hat SEO produces sustainable, long-term results. It contrasts with black hat SEO, which uses deceptive techniques that risk penalties.
XML Sitemap
An XML sitemap is a file that lists all the important pages on your site for search engines to crawl. It includes the URL, last modified date, change frequency, and priority of each page. Submit your sitemap to Google Search Console and keep it updated as you add or remove pages. Use a XML sitemap checker to validate your sitemap before submission.
301 Redirect
A 301 redirect is a permanent redirect from one URL to another. It passes approximately 90-99% of link equity to the new URL. Use 301 redirects when you permanently move a page, change your domain, merge duplicate content, or restructure your site. Avoid redirect chains (multiple 301s in sequence) as they waste crawl budget. Check with a redirect checker.
302 Redirect
A 302 redirect is a temporary redirect. It tells search engines the original URL may come back and they should keep indexing it. 302 redirects pass less link equity than 301s. Use 302 redirects for A/B tests, temporary promotions, or seasonal pages. If a 302 is left in place long enough, Google may start treating it as a 301, which can cause indexing confusion.
404 Error
A 404 error means a page was not found at the requested URL. It can be caused by a deleted page, a broken link, a mistyped URL, or a failed redirect. A small number of 404s is normal, but too many waste crawl budget and create poor user experience. For pages that were permanently removed with valuable backlinks, set up a 301 redirect to a relevant replacement page. Use a redirect checker to find 404s.
Anchor Link
An anchor link (also called a jump link or fragment link) is a link that points to a specific section on the same page using a hash symbol. For example, example.com/page#section-three jumps to the element with id "section-three." Anchor links improve user experience on long pages and can be used in table of contents sections. They do not pass link equity differently from regular internal links.
Bounce Rate
Bounce rate is the percentage of visitors who land on a page and leave without visiting any other page on your site. A high bounce rate can indicate that the page did not meet user expectations or that the site lacks internal linking. However, high bounce rate is not always negative. A blog post that fully answers a question may have a high bounce rate because the user found what they needed. Context matters.
Cloaking
Cloaking is the practice of showing different content to search engines than to users. It is a black-hat technique that violates search engine guidelines. Cloaking can involve serving different HTML based on user agent, hiding text with CSS, or using JavaScript to show different content. It risks severe penalties including complete removal from search results.
Duplicate Content
Duplicate content is content that appears at more than one URL. It can be exact duplicates or near-duplicates with minor variations. Search engines struggle to determine which version to rank, which can dilute ranking signals and reduce visibility. Use canonical tags, 301 redirects, or the noindex directive to handle duplicate content. Check for duplicates with a meta tags checker across multiple URLs.
Evergreen Content
Evergreen content is content that remains relevant and useful long after it is published. Unlike news articles or time-sensitive posts, evergreen content continues to attract search traffic for months or years. Examples include glossaries, how-to guides, checklists, and product comparisons. Creating evergreen content is one of the most effective long-term SEO strategies because the traffic compounds over time.
Heading Hierarchy
Heading hierarchy is the logical structure of heading tags (H1 through H6) on a page. A proper hierarchy has one H1 as the main title, followed by H2 sections, H3 subsections, and so on in order. Skipping heading levels (jumping from H1 to H4) confuses both screen readers and search engines. Use a heading structure checker to verify your hierarchy is correct.
Long-Tail Keyword
A long-tail keyword is a specific, multi-word search query with lower volume but higher intent and lower competition. For example, "best free SEO audit tools for small business" is a long-tail variation of "SEO tools." Long-tail keywords are easier to rank for and often convert better because they match specific user needs. Use a long-tail keyword generator to find them.
Mobile-First Indexing
Mobile-first indexing means Google primarily uses the mobile version of a page for indexing and ranking. If your mobile site has less content than your desktop version, or if mobile usability is poor, your rankings can suffer. Ensure your mobile site has the same content, structured data, and meta tags as the desktop version. Test with Google Search Console mobile usability reports.
Natural Language Processing
Natural language processing (NLP) is a branch of AI that helps search engines understand human language. Google uses NLP models like BERT and MUM to interpret search queries, understand context, and evaluate content quality. This means keyword stuffing is less effective and topical, natural content is rewarded. Write content that answers questions clearly and uses natural language.
PageRank
PageRank is Google original algorithm for ranking web pages based on the quantity and quality of links pointing to them. While the original PageRank toolbar score was deprecated, the underlying concept of link-based authority still influences rankings. Modern link analysis is far more sophisticated, considering link relevance, context, freshness, and trust signals.
Rich Results
Rich results are enhanced search result features that go beyond the standard blue link. They include featured snippets, knowledge panels, FAQ dropdowns, recipe cards, product carousels, and how-to steps. Rich results are triggered by valid structured data (schema markup) on the page. Use a schema markup generator to create the structured data needed for rich results.
Search Volume
Search volume is the number of times a keyword is searched for in a given period (usually monthly). It helps estimate traffic potential for a keyword. High-volume keywords are competitive; low-volume keywords are easier to rank for but may not send much traffic. Balance your keyword strategy between high-volume head terms and lower-volume long-tail variations.
Sitemap Index
A sitemap index is a special sitemap file that points to multiple individual sitemaps. It is used when a site has more than 50,000 URLs or when the sitemap file exceeds 50MB. Search engines read the sitemap index first, then crawl each sub-sitemap. Most CMS platforms generate a sitemap index automatically. Validate it with a XML sitemap checker.
Structured Data
Structured data is a standardized way to provide information about a page and its content to search engines. It is the implementation of schema.org vocabulary, typically in JSON-LD format. Structured data helps search engines understand content relationships and can trigger rich results. Common types include Article, FAQ, Product, LocalBusiness, and HowTo. Use a schema markup generator to create it.
Technical SEO
Technical SEO is the practice of optimizing website infrastructure to help search engines crawl, index, and render pages effectively. It includes site speed optimization, mobile usability, XML sitemaps, robots.txt, canonical tags, redirect management, HTTPS security, and structured data. Technical SEO is the foundation that allows content and links to perform. Without a technically sound site, even great content may not rank.
Topical Authority
Topical authority is the level of trust and expertise a website has demonstrated on a specific topic. Sites that comprehensively cover a topic with multiple related pages, earn relevant backlinks, and publish consistently tend to build topical authority. Google increasingly rewards topical depth over individual page optimization. Building topical authority requires creating content clusters around core topics.
UGC (User-Generated Content)
User-generated content is content created by visitors, customers, or community members rather than the site owner. Examples include comments, forum posts, reviews, and social media embeds. UGC can add fresh, relevant content to a site but may also introduce spam or low-quality links. Use the rel="ugc" link attribute for links within user-generated content to signal they are not editorially endorsed.
Web Crawler
A web crawler (also called a spider or bot) is a program that systematically browses the web to discover and index pages. Search engines use crawlers like Googlebot to find new pages, update existing ones, and follow links. Your robots.txt file tells crawlers which pages to crawl and which to skip. Understanding how crawlers work helps you optimize your site structure and crawl budget.
Core Web Vitals
Core Web Vitals are a set of three metrics that measure real-world user experience for loading performance (LCP), interactivity (INP), and visual stability (CLS). Google uses them as ranking signals. A good site passes all three metrics: LCP under 2.5 seconds, INP under 200 milliseconds, and CLS under 0.1. Use a bulk Core Web Vitals checker to test your pages.
Content Silo
A content silo is a grouping strategy where related content is organized into distinct categories or sections on a site. Each silo focuses on a core topic, with pillar pages and supporting cluster content linked together. Silos help search engines understand site structure and topical relevance. They also improve internal linking by creating clear topic hierarchies.
Domain Rating
Domain rating (DR) is Ahrefs metric that measures the strength of a website backlink profile on a scale of 0 to 100. It is based on the quantity and quality of referring domains. Higher DR domains tend to rank more easily. It is a comparative metric used to evaluate link building opportunities, not a direct ranking factor used by Google.
Exit Page
An exit page is the last page a user visits before leaving your site. Unlike bounce rate (which measures single-page sessions), exit rate measures how often users leave from a specific page after visiting multiple pages. A high exit rate on a key page (like a product page or contact page) may indicate that the page needs better calls to action or internal links to keep users engaged.
Keyword Cannibalization
Keyword cannibalization occurs when multiple pages on your site compete for the same keyword. Instead of one strong page ranking, Google splits attention between several weaker pages, and none rank as well as they could. The solution is to consolidate competing pages using 301 redirects, canonical tags, or by merging content into a single comprehensive page.
Link Building
Link building is the practice of acquiring backlinks from other websites to your own. It remains one of the most important ranking factors. Effective link building strategies include creating link-worthy content (original research, tools, comprehensive guides), guest posting on relevant sites, digital PR, and building relationships with industry bloggers. Avoid buying links or participating in link schemes.
Pillar Page
A pillar page is a comprehensive, authoritative page that covers a broad topic in depth. It links to more specific cluster content pages that cover subtopics in detail. Pillar pages form the hub of a content silo strategy. For example, a pillar page on "SEO Tools" might link to cluster pages about audit tools, keyword tools, link building tools, and rank trackers.
Position Zero
Position zero is the spot above the first organic search result, typically occupied by a featured snippet, knowledge panel, or other rich result. Ranking in position zero can significantly increase visibility and click-through rate. To optimize for position zero, structure content with clear question-and-answer formats and use schema markup.
Referring Domain
A referring domain is a unique website that links to your site. Multiple backlinks from the same referring domain count as one referring domain. The number and quality of referring domains is a stronger ranking signal than the total number of backlinks. One link from a high-authority, relevant referring domain is worth more than 100 links from a single low-quality site.
Search Intent
Search intent is the goal behind a search query. Understanding whether a user wants information, wants to navigate to a specific site, is comparing options, or is ready to buy is essential for creating content that ranks. Match your content format and depth to the intent: informational queries need comprehensive guides, transactional queries need product pages with clear CTAs.
Site Architecture
Site architecture is the structure and organization of pages on your website. Good site architecture ensures every page is reachable within a few clicks from the homepage, uses a logical URL hierarchy, and employs internal linking to distribute authority. A flat architecture (few levels deep) is preferred over deep nesting. Use XML sitemaps and breadcrumbs to reinforce your architecture.
SSL Certificate
An SSL certificate enables HTTPS encryption on your site, securing data between the user browser and your server. HTTPS is a confirmed Google ranking signal and a baseline trust indicator. An expired certificate, mixed content warnings, or missing SSL undermines both security and SEO. Use a SSL checker to verify your certificate is valid and unexpired.
Vertical Search
Vertical search is a search engine that focuses on a specific type of content rather than the general web. Examples include Google Images, Google News, YouTube, Amazon product search, and Yelp. Optimizing for vertical search means understanding the specific requirements of each platform. Image SEO, video SEO, and product feed optimization are all forms of vertical search optimization.
Algorithm Update
An algorithm update is a change to the formulas search engines use to rank pages. Google makes thousands of updates per year, but only a few are major broad core updates that significantly impact rankings. Staying informed about major updates helps you understand ranking changes and adjust your strategy. Focus on creating high-quality content and a technically sound site, which are resilient to algorithm changes.
Crawl Error
A crawl error occurs when a search engine crawler cannot access a page on your site. Common causes include server errors (5xx), soft 404s, redirect chains, and blocked resources. Crawl errors prevent pages from being indexed and can indicate technical issues. Monitor crawl errors in Google Search Console Coverage report and fix them promptly.
Deindexed
Deindexed means a page or domain has been removed from a search engine index and will no longer appear in search results. Deindexing can happen manually (via noindex tag), through robots.txt blocking, or as a penalty for violating guidelines. A manual action penalty can deindex entire sections of a site. Check your index status in Google Search Console.
FAQ Schema
FAQ schema is a type of structured data that marks up questions and answers on a page. When implemented correctly, it can trigger FAQ rich results in Google search, showing expandable Q&A dropdowns directly in the results. FAQ rich results increase SERP visibility and click-through rate. Use a schema markup generator to create valid FAQ JSON-LD.
Googlebot
Googlebot is Google web crawler that discovers and indexes pages on the web. It follows links, reads sitemaps, and renders pages to understand content. Googlebot respects robots.txt directives and noindex tags. You can manage how Googlebot interacts with your site through robots.txt, meta robots tags, and the URL Inspection tool in Google Search Console.
Impressions
An impression is recorded each time a page appears in search results (whether or not it is clicked). High impressions with low clicks indicates a CTR problem that can be fixed by improving title tags and meta descriptions. Low impressions may indicate the page is not ranking for the targeted keywords. Track impressions in Google Search Console Performance report.
Keyword Gap
A keyword gap is the set of keywords your competitors rank for but you do not. Identifying and filling keyword gaps is one of the fastest ways to increase organic traffic. Use a keyword gap analysis tool to compare your domain against competitors and find opportunities. Then create comprehensive content targeting each gap keyword cluster.
Latent Semantic Indexing (LSI)
LSI refers to mathematical techniques that identify relationships between terms and concepts in text. While Google has stated it does not use traditional LSI, the concept of semantic relevance is important. Using related terms, synonyms, and contextual language helps search engines understand your content. Write naturally and cover topics thoroughly rather than obsessing over specific LSI keywords.
Outbound Link
An outbound link (also called an external link) is a link from your site to another website. Outbound links add credibility when they point to authoritative sources and help search engines understand the context of your content. Linking to relevant, high-quality external sites is a good SEO practice. It does not significantly reduce your own page authority.
Page Authority
Page authority is a metric (originally from Moz) that predicts how well a specific page will rank. It is based on the page link profile, content quality, and other on-page factors. Like domain authority, it is a comparative metric. Focus on building backlinks to individual pages and optimizing on-page elements to increase page authority over time.
Query
A query is the text a user types into a search engine. Understanding the queries that bring users to your site is fundamental to SEO. Google Search Console shows which queries trigger impressions and clicks for your pages. Analyzing query data helps you identify content gaps, understand user intent, and optimize existing pages for higher click-through rates.
Referral Traffic
Referral traffic is visitors who arrive at your site by clicking a link on another website (as opposed to organic search, paid search, or direct traffic). Referral traffic from relevant, authoritative sites can improve your SEO through brand signals and potential link building opportunities. Track referral traffic in Google Analytics to identify valuable link sources.
SERP Feature
SERP features are non-standard elements that appear in search results alongside or instead of traditional organic listings. Examples include featured snippets, knowledge panels, image packs, video carousels, People Also Ask boxes, and local packs. Each feature has specific optimization requirements. Understanding which SERP features appear for your target keywords helps you choose the right content format.
Status Code
A status code is a three-digit number returned by a server in response to a request. The most important for SEO are 200 (OK), 301 (permanent redirect), 302 (temporary redirect), 304 (not modified), 404 (not found), and 500 (server error). Monitoring status codes helps you detect broken links, redirect issues, and server problems. Use a redirect checker to verify status codes.
TF-IDF
TF-IDF (Term Frequency-Inverse Document Frequency) is a statistical measure that evaluates how important a word is to a document relative to a collection of documents. In SEO, TF-IDF analysis helps you understand which terms are used frequently by top-ranking pages for a keyword, indicating topics and language you should cover. It is a tool for content optimization, not a direct ranking factor.
This glossary covers the foundational vocabulary of SEO. As search engines evolve, new terms will emerge and existing definitions will shift. Bookmark this page and revisit it as you encounter unfamiliar concepts in your SEO journey.
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