Defined Terms

A controlled experiment comparing two versions to see which performs better.

The visible, clickable words in a hyperlink, used as a relevance signal.

A defined contract that lets two software systems talk to each other in a predictable way.

Assigning credit for a conversion across the touchpoints that led to it.

A link from another website to yours, treated as a signal of trust and relevance.

An HTML hint that tells search engines which URL is the master version of a page.

The gradual loss of traffic and rankings a page suffers as it ages and the SERP moves on.

The share of visitors who complete a desired action.

Google's field-data metrics for loading, interactivity and visual stability.

The average amount you pay each time someone clicks your ad.

How many pages a search engine will crawl on your site, and how often.

A structured process for increasing the share of visitors who convert.

The share of people who click after seeing your ad or search result.

A third-party score estimating the strength of a domain’s backlink profile.

Experience, Expertise, Authoritativeness and Trust — Google’s quality framework.

A measure of how actively people interact with content or a page.

A highlighted answer box pulled from a ranking page to the top of the SERP.

Optimising content to be cited and surfaced by AI answer engines, not just ranked in blue links.

A content system that stores and serves content via API, leaving the front end entirely to you.

The step where client JavaScript attaches to server-rendered HTML to make it interactive.

Whether a page is stored in a search engine’s index and eligible to rank.

Links between pages on your own site, used to spread authority and context.

When multiple pages on one site compete for the same query, weakening all of them.

An AI model trained on vast text to predict and generate language, powering tools like ChatGPT.

A proposed plain-text file that gives AI models a curated, easy-to-read map of your site's content.

A longer, more specific search query with lower volume but clearer intent and less competition.

The ratio of a customer’s lifetime value to the cost of acquiring them.

A content structure where a broad pillar page links to focused cluster pages that link back.

Google Ads’ 1-to-10 rating of the quality and relevance of your keywords and ads.

Grounding an LLM's answers in retrieved documents so it responds from real, current data.

Revenue generated for every unit of currency spent on advertising.

A root-level file that tells crawlers which URLs they may or may not fetch.

The underlying goal behind a search query, which content must satisfy to rank.

The Search Engine Results Page — everything a search engine returns for a query.

Rendering a page's HTML on the server so it arrives ready to display, before JavaScript runs.

Machine-readable markup that describes page content to search engines.

The credibility a site earns with search engines by covering a subject deeply and consistently.

A machine-readable list of your important URLs, submitted to help discovery.