Letter D9 terms in the glossary

An organized set of design rules: palette, typography, grid, interface components, and patterns for using them. It replaces decisions that would otherwise be made from scratch for every screen.

It delivers the most value at the intersection of design and development - designers and developers work from the same names and values, so fewer things get lost along the way.

Lets a site owner report to Google a list of links they do not want counted in the site's evaluation. Useful when a site has fallen victim to mass linking from spammy domains.

A last-resort tool, not a routine one. Disavowing valuable links by mistake can lower visibility more than the links you meant to remove - which is why it is preceded by an analysis of the entire link profile.

The layer that translates a memorable domain name into the IP address where the server actually sits. Thanks to it, changing hosting does not require changing the site's address.

DNS misconfigurations are among the most costly, since they result in the entire site and email being unavailable. Changes can take up to several dozen hours to propagate, so they should be planned in advance.

A unique name typed into the browser's address bar. It is registered with a registrar for a set period and renewed - expiry means the site and company email disappear.

The domain should be registered in the client's name, not the agency's or the contractor's. That is the one record that actually determines who owns the address.

A signup model where, after filling in a form, the user receives a message asking them to confirm. Only clicking that link completes the subscription.

It shrinks the list at the start but raises its quality and deliverability. It also protects against signing someone up to an address that is not theirs - which, without confirmation, can be treated as spam.

A measure of domain authority calculated by Ahrefs based on the number and quality of inbound links. Used mainly to compare sites against each other and to assess the value of a potential link placement.

A commercial metric, not an official one - Google does not publish or use it. A high DR does not guarantee rankings, just as a low one does not rule them out.

A model where the seller takes the order and passes it to a supplier, who ships the goods directly to the customer. It lets you start selling without investing in stock or a warehouse.

The price for that low entry barrier is a lack of control over shipping time, packaging quality, and returns - that is, over everything the customer judges after the purchase. Complaints land with the seller, not the supplier.

Content available at more than one address. Internal duplicates arise most often from filters, sorting, and parameterized URL versions; external ones from multiple sellers copying manufacturer descriptions.

A search engine has to pick one version to show, and it makes that call itself. Pointing it to the right one with a canonical tag takes that decision out of chance's hands.

The length of time a user stays on a page before going back to the search results. A short dwell time can signal that the content does not match the query that brought the user there.

Google does not confirm using this metric outright, so it is treated as a diagnostic clue, not a goal in itself. Artificially padding time on page does not improve anything.