What this guide will help you do
Give marketers and site owners clear definitions they can use while reading audits and Search Console reports.
Key takeaways
- Crawling, indexing, and ranking are separate stages.
- A metric describes evidence; it rarely explains the cause by itself.
- Use this glossary alongside the linked practical guides when a term affects your site.
A–C: authority, backlinks, canonicals, and crawling
Authority is an informal description of a site's or creator's reputation; Google does not publish one universal authority score. A backlink is a link from another site. A canonical is the preferred URL among duplicate or near-duplicate versions. Crawling is the process of discovering and fetching URLs.
A cache stores reusable files or responses to reduce repeat work. A citation is an online mention of a business, often including its name, address, and phone. CLS, or Cumulative Layout Shift, measures unexpected visual movement while a page is used.
D–I: duplicate content, impressions, indexing, and intent
Duplicate content is substantially similar material available at more than one URL. An impression records search-result visibility under a platform's reporting rules. Indexing is the process of analysing and storing a page so it can be considered for search results.
Search intent is the job a person wants to complete, such as learning, comparing, visiting, or buying. An internal link connects pages on the same site. INP, or Interaction to Next Paint, measures how responsive a page is across user interactions.
K–R: keywords, LCP, noindex, robots, and redirects
A keyword is a word or phrase connected to a search need; it is not an instruction to repeat that phrase. LCP, or Largest Contentful Paint, measures when the main visible content finishes rendering. A noindex directive asks compliant search engines not to index a page.
Robots.txt controls crawler access but is not a reliable removal method for indexed URLs. A redirect sends a request to another URL. Ranking is the ordering process for a specific search context, not a permanent property of a page.
S–Z: schema, sitemaps, snippets, and URL status
Schema markup is structured vocabulary used to describe entities and properties. An XML sitemap lists preferred URLs for discovery. A snippet is the title, description, and other elements shown for a result; search engines may generate it from page content.
A 200 status means a request succeeded, 301 means a permanent redirect, 404 means the resource was not found, and 5xx statuses indicate server errors. SEO connects these technical signals with useful content, credible promotion, and a good visitor experience.
A practical next-step checklist
- Separate crawl, index, and ranking problems in every diagnosis.
- Check the source of any metric before comparing it.
- Use precise terms in tickets and reports.
- Follow the related guides when a definition reveals an issue.
When you make a technical change, test a small group of representative URLs first. Then run the free SEO audit to catch broken links, metadata gaps, crawl signals, and page-level regressions before applying the change across the whole site.
Frequently asked questions
What does SEO stand for?
SEO stands for search engine optimisation: improving a site's accessibility, relevance, usefulness, and reputation so it can earn appropriate organic visibility.
What is the difference between crawling and indexing?
Crawling is fetching a URL. Indexing is analysing and storing its content for possible use in search results. A crawled page is not automatically indexed.
What is a SERP?
SERP means search engine results page—the page containing organic results, ads, maps, images, answers, and other search features.
Primary references
Use these first-party references to confirm details that may change after this guide is published: