Overlays & Surfaces
Modal Dialog
also known as blocking dialog
A modal dialog is a dialog displayed with modal behavior: the rest of the screen is disabled (usually dimmed by a scrim) and you must act on the dialog before returning to your work. It's the most common overlay for confirmations, forms, and important decisions. Focus is trapped inside it for keyboard and screen-reader users.
See it live — shadcn/ui · MUI · Ant Design
Don't confuse it with
A modal dialog is the specific combination: a dialog (component) plus modal (blocking behavior). A plain 'dialog' may or may not be modal. A non-modal dialog is the same component without blocking. An alert dialog is a modal dialog reserved for urgent messages.
In the wild
Deleting a repository on GitHub opens a modal dialog you must confirm before anything else.