Tooltip
A tiny label that appears when you hover over or focus something, explaining what it is.
What it is
A tooltip is a small text bubble that shows up when you point at an element, usually an icon, and disappears when you move away. It answers "what does this do?" without cluttering the screen.
Keep tooltips to a few words, and never put anything essential in one: phones have no hover, so touch users may never see it. Icon-only buttons are the classic use.
A tooltip only shows text. If it needs buttons or a form, it's a popover.
How to ask for it
“People don't know what the icons mean. Can it say what they are somehow?”
“Add a tooltip to every icon-only button in the toolbar showing its name (for example "Bold"), appearing after a 500ms hover or on keyboard focus, positioned above the icon.”
"Say what they are somehow" could mean permanent labels; "tooltip" names hover-only hints and the prompt covers delay, focus, and placement.
You've seen this in
- GHovering the toolbar icons in Google Docs
- YThe "Copy link" hint on YouTube's share button
- DHovering a truncated file name in Dropbox