A number of predefined brush types are available in Paint including round, square, and elliptical brushes of various sizes and edge softness. The cursor has the same appearance regardless of which brush type you use. Each brush has its own icon in the Brushes window. The white portions of the brush icon indicate where the paint will be applied on the image. See
To select a brush:
To scroll the selections, click the Brushes window and drag left or right.
The selected brush is highlighted by a blue outline.