There are many different types of bob hairstyles, including the graduated bob, long bob and chin-length bob. Each style flatters a different face shape, according to About.com, and may be worn with or without bangs.
Tapered chin-length bobs flatter heart-shaped faces because they harmonize the full cheeks and pointy chin that characterize this face shape. Long, layered bobs are preferable for women with long faces, and sideswept bangs make high foreheads appear less prominent. Both straight and wavy bobs flatter long faces. For the best results, the end of the bob should be directly below the jawline.
Graduated bobs work best on square faces. This type of bob has a short back and becomes progressively longer toward the chin. The longest layers should end about 2 inches below the chin.