Tobiano
(pronounced: tow be yah' no)

The dark color usually covers one or both flanks.

Generally, all four legs are white, at least below the hocks and knees.

Generally, the spots are regular and distinct as ovals or round patterns that extend down over the neck and chest, giving the appearance of a shield.

Head markings are like those of a solid-colored horse--solid, or with a blaze, strip, star or snip.

A tobiano may be either predominantly dark or white. The tail is often two colors.

Overo
(pronounced: oh vair' oh)

The white usually will not cross the back of the horse between its withers and its tail.

Generally, at least one and often all four legs are dark.

Generally, the white is irregular, and is rather scattered or splashy.

Head markings are distinctive, often bald-faced, apron-faced or bonnet-faced.

An overo may be either predominantly dark or white.  The tail is usually one color.