Dogs (Canis lupus familiaris) are loyal, lovable, and incredibly diverse companions. Here's a general Body: Muscular, varied in size and shape, from small toy breeds to large working breeds.br - Coat: Wide range of lengths, textures, and colors, from short and smooth to long and fluffy.br - Head: Shapes and sizes vary, with different ear types (floppy, erect, or semi-erect) and muzzle lengths.