Progress Bar

A UI element that visually communicates the proportion of a task, process, or timeline that has been completed. In media players it indicates playback position; in forms and wizards it signals completion across steps; in file transfers it shows elapsed progress. Accessibility requirements include an accessible name, current/total values exposed via ARIA (role="progressbar", aria-valuenow, aria-valuemin, aria-valuemax), non-color-only indication of progress, and — for determinate bars — a textual equivalent. Valuable for users with cognitive disabilities, aphasia, or anxiety because visible completion reduces uncertainty and builds confidence.