The Note tool (symbolized by a yellow notepad) allows you to attach a note to an image. It is similar to a Text Rollup.
The Text tab in the Note properties dialog allows you to set the text contents of the box, along with color and alignment options.
The Pen tab in the Note properties dialog allows you to set options for the width, color, and style of that box.
The Brush tab in the Note properties dialog allows you to set the type and color of the brush that will fill in that shape.
The Font tab in the Note properties dialog allows you to set the font for that box.