Originating from the red record button on old video cameras, this emoji is now also widely used as an icon to signal the start of a live broadcast. It indicates a 'now broadcasting' status.

Beyond simple recording, it's also used declaratively to mean 'it's starting now' or 'let's get serious.' It enriches expression when used to show determination before starting a project or an important presentation, like 'Okay, let's begin ⏺️'.