Glossary
No jargon, no assumed knowledge. Every term you'll run into using Site Structure (or reading an SEO audit anywhere else) defined in plain English.
A group of pages on a site that all cover the same subject and link to each other. Search engines use silos as a signal of topical authority: a site with a tight, well-linked cluster of pages about one subject tends to rank better for that subject than one with the same pages scattered and disconnected.
A topic your site should cover (because competitors rank for it, or because it fits an existing silo) but currently doesn't have a page for. Closing content gaps is one of the fastest ways to grow organic traffic, since you're targeting demand that's already proven to exist.
A page on your site with no internal links pointing to it from anywhere else on the site. Search engines discover and rank pages partly through the links between them, so an orphaned page is much harder to find and rank, even if the content itself is good.
A hyperlink from one page on your site to another page on the same site (as opposed to a link to an external website). Internal links help both visitors and search engines navigate your site, and they pass authority between pages: a well-linked page tends to rank better than an identical page with no internal links pointing to it.
The main, most comprehensive page in a topical silo, usually the one you want to rank for the broadest version of a topic. Supporting pages in the silo link back to the pillar, and the pillar links out to them, concentrating relevance and authority on the topic as a whole.
A short outline for a piece of content before it's written: the target topic, suggested headings, and the gap or keyword it's meant to close. Briefs turn a vague "we should write about X" into something a writer can act on directly.
A set of keywords that are closely related in meaning and search intent, such that a single page could reasonably target all of them at once instead of needing a separate page for each. Clustering keywords first prevents you from accidentally writing multiple pages that compete with each other for the same search results.
Comparing your site's content against a competitor's to find topics they rank for that you don't have a page for at all. It's a fast way to find content ideas that are already proven to attract search traffic in your space.
An HTML tag that tells search engines which version of a page is the "real" one when the same or very similar content is reachable at more than one URL (for example, with and without a trailing slash, or with tracking parameters). Without it, search engines may split ranking signals across duplicate URLs instead of crediting one canonical page.
A short snippet of HTML that summarizes a page's content. It doesn't directly affect rankings, but it's often shown as the description text under your page's link in search results, so a clear, compelling one can improve your click-through rate.
The HTML element that sets a page's title, shown as the clickable headline in search results and as the browser tab label. It's one of the strongest on-page ranking signals, and should clearly describe what the page is about.
A short text description attached to an image in HTML. It's read aloud by screen readers for visually impaired visitors, shown if the image fails to load, and used by search engines to understand what an image contains, since they can't "see" images the way a person can.
Extra code added to a page (commonly in a format called JSON-LD) that explicitly labels what the content means: this is a product, this is its price, this is a review, this is a recipe with these ingredients. Search engines use it to build richer search results, like star ratings or FAQ dropdowns, directly in the results page.
An HTML tag that tells a browser how to scale a page's width on different screen sizes. It's what makes a site render correctly on a phone instead of showing a shrunken desktop layout. Missing it is a common technical SEO issue since search engines prioritize mobile-friendly pages.
A set of metrics Google uses to measure real-world page experience: how fast the main content loads, how quickly the page responds to input, and how much the layout shifts around while loading. Poor Core Web Vitals scores can hold back rankings even if the content itself is strong.
A rule that automatically sends visitors (and search engines) from one URL to another. A 301 redirect means "this page has permanently moved," and passes most of the original page's ranking signals to the new URL. A 302 means "this is temporary," and search engines generally keep indexing the original URL instead.
A 404 is the error a browser shows when it requests a page that doesn't exist. A broken link is any link, internal or external, that points to a URL returning a 404 (or another error). Broken links waste the value of any traffic or links pointing at them, and hurt user experience.
A crawler (or "bot") is an automated program search engines use to visit pages, follow the links on them, and discover new pages across the web. "Crawling" a site means having a bot systematically visit its pages, which is the first step before any page can be indexed or ranked.
Indexing is a search engine storing a page in its database so it's eligible to appear in results at all. Ranking is deciding where that page appears, relative to others, for a given search. A page can be indexed but rank poorly, and a page that isn't indexed can't rank no matter how good it is.
A file, usually at /sitemap.xml, listing the URLs on a site that you want search engines to know about. It doesn't guarantee those pages get indexed, but it makes them easier to discover, especially on large sites or sites with pages that aren't well linked internally.
A file at the root of a site (yoursite.com/robots.txt) that gives crawlers instructions about which parts of the site they're allowed to visit. It's a request, not a hard security barrier: well-behaved crawlers like Googlebot respect it, but it doesn't prevent access on its own.
The page a search engine shows after someone runs a search: the list of ranked results, along with anything else shown alongside them (ads, featured snippets, maps, images). "Ranking on page one of the SERP" means appearing in the first page of organic results for a given search.
A link from another website pointing to a page on your site. Search engines treat backlinks, especially from relevant, trustworthy sites, as a vote of confidence, making them one of the strongest ranking factors outside of the content itself.
The clickable, visible text of a hyperlink. Anchor text gives both readers and search engines a hint about what the linked page is about, so descriptive anchor text ("our pricing plans") is more useful than generic text ("click here") for both usability and SEO.