Captions are a way to help you organize your clips in the Clip Organizer. They do not appear in or with your clip when you insert it into a file, and do not modify the image in any way.
To include a caption with your clip after you have inserted it in your file, see these product-specific instructions:
Add or change a caption
Open the Clip Organizer if you are not already in it.
Select a clip from the My Collections folder.
On the Edit menu, click Keywords.
Under the clip preview, in the Caption list, type the caption you want.
Note: The caption is visible as a ToolTip when you rest the mouse pointer on a clip.