The Paint Brush Tool lays down pixels on the page, creating strokes with antialiased edges. This creates a natural transition between the stroke and the surrounding pixels.
Its variable width lines can be controlled either by velocity—most useful when drawing with a mouse—or by pressure—for use when drawing with a pressure-sensitive device.
Other brush-based tools use similar settings to control the appearance of the applied pixels, although there may be slight variations.
Most brushes use a soft, round brush as their default. Alternative styles can be selected from the Brushes panel.
The following settings can be adjusted from the context toolbar: