Glossary

Technical SEO Terms

69 essential terms covering crawling, indexing, site architecture, Core Web Vitals, structured data, and server configuration.

Crawling & Indexing URL & Redirect Management Core Web Vitals & Performance Site Architecture Structured Data & Rich Results Server & Hosting Mobile & International

13Crawling & Indexing

Crawling: The process by which search engine bots (spiders/crawlers) discover and download web pages by following links. Googlebot is Google's primary crawler.
Indexing: The process of storing and organizing crawled content in a search engine's database so it can be retrieved for relevant queries. A page must be indexed to appear in search results.
Crawl Budget: The number of pages a search engine will crawl on your site within a given timeframe. Affected by site size, page speed, server capacity, and URL importance.
Crawl Rate: The speed at which search engine bots request pages from your server. Can be adjusted in Google Search Console to prevent server overload.
Crawl Depth: How many levels deep into your site architecture a crawler will go. Important pages should be within 3-4 clicks of the homepage.
Robots.txt: A text file at your domain's root that tells search engine crawlers which pages or sections they can or cannot access. Uses Disallow and Allow directives.
XML Sitemap: An XML file listing important URLs on your site to help search engines discover and crawl content efficiently. Should be submitted to Google Search Console.
Sitemap Index: A sitemap that references multiple sitemap files. Required when you have more than 50,000 URLs or your sitemap exceeds 50MB.
Noindex: A meta robots directive telling search engines not to include a page in their index. Use for thank you pages, admin areas, or duplicate content.
Nofollow: A link attribute or meta directive telling search engines not to pass PageRank through a link or follow links on a page.
Index Bloat: When search engines index too many low-value or duplicate pages, diluting your site's overall quality signals and wasting crawl budget.
Orphan Pages: Pages that have no internal links pointing to them, making them difficult for crawlers and users to discover.
Crawl Errors: Issues that prevent search engines from accessing pages, including 404 errors, server errors, redirect errors, and blocked resources.

10URL & Redirect Management

301 Redirect: A permanent redirect that passes 90-99% of link equity to the destination URL. Use when pages are permanently moved or domains are changed.
302 Redirect: A temporary redirect that may not pass full link equity. Use only for genuinely temporary situations like A/B testing or maintenance.
307 Redirect: An HTTP status code for temporary redirects that preserves the request method. The HTTP/1.1 equivalent of 302.
308 Redirect: A permanent redirect that preserves the request method. The permanent equivalent of 307.
Redirect Chain: When one redirect leads to another redirect, creating a chain. Each hop in the chain can slow page load and dilute link equity. Keep chains under 3 hops.
Redirect Loop: When redirects create a circular pattern (A→B→A), causing pages to never load. A critical error that must be fixed immediately.
Canonical URL: The preferred version of a page when multiple URLs contain similar content. Specified with rel="canonical" link element to consolidate ranking signals.
Self-Referencing Canonical: A canonical tag that points to the same URL it's on. Considered a best practice to explicitly declare the preferred version.
URL Parameter Handling: Configuration telling search engines how to handle URL parameters (sorting, filtering, tracking). Set in Google Search Console or via robots.txt.
Clean URLs: URLs without excessive parameters, session IDs, or unnecessary characters. Improves user experience and click-through rates.

11Core Web Vitals & Performance

Core Web Vitals: Google's set of user experience metrics: LCP (loading), FID/INP (interactivity), and CLS (visual stability). Part of page experience ranking signals.
Largest Contentful Paint (LCP): Measures loading performance—the time it takes for the largest content element to become visible. Target: under 2.5 seconds.
First Input Delay (FID): Measures interactivity—the time from when a user first interacts to when the browser responds. Target: under 100ms. Being replaced by INP.
Interaction to Next Paint (INP): Measures overall page responsiveness throughout the user's visit, not just first interaction. Replaced FID in March 2024. Target: under 200ms.
Cumulative Layout Shift (CLS): Measures visual stability—unexpected layout shifts during page load. Caused by images without dimensions, dynamic content, web fonts. Target: under 0.1.
Time to First Byte (TTFB): The time from the user's request to receiving the first byte of response. Affected by server performance, CDN, and backend processing. Target: under 800ms.
First Contentful Paint (FCP): The time when the first content element (text, image) is rendered. An early indicator of perceived loading speed.
Total Blocking Time (TBT): The total time between FCP and Time to Interactive when the main thread was blocked. Lab metric correlating with FID.
Speed Index: Measures how quickly content is visually displayed during page load. Lower scores indicate faster perceived performance.
Critical Rendering Path: The sequence of steps the browser takes to convert HTML, CSS, and JavaScript into pixels on screen. Optimizing this improves perceived performance.
Render-Blocking Resources: CSS and JavaScript files that prevent the page from rendering until they're loaded. Should be minimized or deferred.

7Site Architecture

Site Architecture: The hierarchical structure of pages and how they're organized and linked together. Affects crawlability, user experience, and link equity distribution.
Flat Architecture: A site structure where most pages are few clicks from the homepage. Ensures important pages are easily discoverable and receive more link equity.
Silo Structure: Organizing content into themed categories with strong internal linking within each silo and limited cross-linking between silos.
Hub and Spoke Model: A content architecture with a central pillar page (hub) linking to related subtopic pages (spokes), which link back to the hub.
Faceted Navigation: Navigation allowing users to filter results by multiple attributes (size, color, price). Can cause index bloat if not properly managed.
Pagination: Splitting content across multiple pages. Use rel="next"/rel="prev" (deprecated but still useful) or load more/infinite scroll with proper implementation.
JavaScript Navigation: Navigation built with JavaScript that may not be crawlable by search engines. Ensure important links are in the HTML or use server-side rendering.

11Structured Data & Rich Results

Structured Data: Standardized code (usually JSON-LD) that helps search engines understand page content and enables rich results in SERPs.
Schema.org: A collaborative vocabulary for structured data markup, supported by Google, Bing, Yahoo, and Yandex.
JSON-LD: JavaScript Object Notation for Linked Data—Google's preferred format for structured data. Placed in a <script> tag in the page head or body.
Rich Results: Enhanced search results with additional visual elements like stars, images, prices, or FAQs. Enabled by structured data.
Featured Snippets: Highlighted boxes at the top of search results showing extracted content that directly answers a query. Position zero.
Knowledge Panel: Information boxes appearing on the right side of search results for entities (people, places, organizations, things).
FAQ Schema: Structured data markup for frequently asked questions, enabling expandable Q&A in search results.
How-To Schema: Structured data for step-by-step instructions, enabling rich results with images and steps.
Product Schema: Structured data for products including price, availability, and reviews. Enables rich product snippets.
Article Schema: Structured data for news articles, blog posts, and other article content. Can enable rich results and Google News inclusion.
Breadcrumb Schema: Structured data that shows page hierarchy in search results, improving click-through rates and user understanding.

9Server & Hosting

HTTP Status Codes: Three-digit codes indicating the result of a server request. 200 (OK), 301 (Permanent Redirect), 404 (Not Found), 500 (Server Error), etc.
HTTPS: Secure HTTP using SSL/TLS encryption. A ranking factor since 2014. All sites should use HTTPS for security and SEO.
SSL Certificate: A digital certificate that enables HTTPS encryption. Available free from Let's Encrypt or paid from certificate authorities.
CDN (Content Delivery Network): A network of servers distributed globally to deliver content from locations closer to users. Improves page speed and reliability.
Server Response Time: How quickly your server responds to requests. Affected by hosting quality, database optimization, and code efficiency.
Edge Computing: Processing data closer to the user at the network edge, reducing latency. Used by modern CDNs and serverless platforms.
Caching: Storing copies of pages or resources for faster retrieval. Includes browser caching, server caching, and CDN caching.
Gzip/Brotli Compression: Server-side compression that reduces file sizes for faster transfer. Brotli typically achieves 20-26% better compression than Gzip.
HTTP/2 and HTTP/3: Modern HTTP protocols enabling faster page loads through multiplexing, header compression, and (HTTP/3) improved connection handling.

8Mobile & International

Mobile-First Indexing: Google primarily uses the mobile version of content for indexing and ranking. All sites are now on mobile-first indexing.
Responsive Design: A design approach where layouts adapt to different screen sizes using CSS media queries. Google's recommended mobile configuration.
AMP (Accelerated Mobile Pages): A Google-backed framework for fast-loading mobile pages. No longer required for Top Stories but still useful for specific use cases.
Mobile Usability: How well a site functions on mobile devices. Issues include small tap targets, horizontal scrolling, and unplayable content.
Hreflang: HTML attribute telling search engines which language and regional targeting a page uses. Essential for international SEO.
ccTLD: Country Code Top-Level Domain (e.g., .uk, .de, .fr). Provides strong geographic signals but requires separate domain management.
Subdirectory vs Subdomain: International content can use subdirectories (example.com/de/) or subdomains (de.example.com). Subdirectories consolidate domain authority.
Geotargeting: Targeting content to users in specific geographic locations. Set in Google Search Console for generic TLDs.

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