Glossary
SEO terms, in plain words
Each term starts with a definition you can quote, then the explanation, and then what Lastmod does with it, if anything.
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All terms
- AI Mode
- AI Mode is a way of searching Google in which an AI assistant writes an answer to your question, in conversation, with links to the sources it used.
- AI Overview
- An AI Overview is a summary written by AI that Google shows at the top of some search results, with links to the pages it drew on.
- Baseline window
- A baseline window is the period before a change that serves as the reference. The days after the change are compared with it to see whether anything moved.
- Canonical tag
- A canonical tag is a line in a page's HTML that names the preferred URL for that page, so search engines know which version to show and count.
- Click-through rate (CTR)
- Click-through rate is the share of impressions that lead to a click: clicks divided by impressions, usually shown as a percentage.
- Confounded result
- A confounded result is a before-and-after change that something other than your edit could explain, such as another change on the same page or a site-wide shift.
- Core Web Vitals
- Core Web Vitals are three measures of page experience: how fast the main content loads (LCP), how quickly the page responds to input (INP), and how much it shifts while loading (CLS).
- Crawl budget
- Crawl budget is the number of pages a search engine is willing and able to fetch from your site in a given period, set by how fast your server responds and how much your pages seem worth fetching.
- CTR decoupling
- CTR decoupling is a page keeping its impressions and its position while its click-through rate falls, so rankings and clicks stop moving together.
- Generative engine optimization (GEO)
- Generative engine optimization (GEO) is the work of making a site easy for AI assistants such as ChatGPT to find, read and cite when they answer a question.
- hreflang
- Hreflang is a set of links that tells search engines which language or regional versions of a page exist, so they can show each visitor the fitting one.
- IndexNow
- IndexNow is an open protocol that lets a site notify participating search engines straight away when a page is added, changed or removed, instead of waiting for them to crawl it.
- Keyword cannibalization
- Keyword cannibalization is when several pages of the same site compete for the same search terms, so search engines have to pick between them and clicks are spread out.
- lastmod (sitemap)
- Lastmod is an element in an XML sitemap that gives the date a page was last changed in a meaningful way, so search engines can decide when to crawl it again.
- llms.txt
- Llms.txt is a proposed convention: a Markdown file at /llms.txt that gives AI assistants a short description of a site and links to its most useful pages.
- Meta description
- A meta description is a short summary of a page in its HTML head. Search engines often show it under the title in the results.
- Minimum-traffic gate
- A minimum-traffic gate is a rule that no result is calculated when the traffic behind it is too small, so a thin dataset never produces a precise-looking percentage.
- noindex
- Noindex is an instruction, in a robots meta tag or an X-Robots-Tag header, that tells search engines not to show a page in their results.
- Quick win
- An SEO quick win is a page that ranks close to the first page and gets many impressions but few clicks, so a small change to its title or description may help.
- Result confidence
- Result confidence is a label (high, medium, low or inconclusive) that says how reliable a measurement is, based on how much traffic there was and how large the change was.
- robots.txt
- Robots.txt is a plain-text file at the root of a site that tells crawlers which paths they may fetch. It controls crawling, not whether a page appears in search results.
- Search intent
- Search intent is what a person is trying to get done with a query: to learn something, to find a specific site, to compare options, or to buy.
- Structured data
- Structured data is markup, usually JSON-LD in the page's HTML, that states in a fixed vocabulary what a page is about, such as a product, an article or a business.
- Title tag
- The title tag is the page title in the HTML head. It is the headline search engines usually show for your page in the results.
- Wilson interval
- A Wilson interval is a range around a percentage that shows how far it could really lie from the true value, given how few answers it is based on.
- XML sitemap
- An XML sitemap is a file that lists the URLs you want search engines to know about, so they can find pages and see when they last changed.
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