Men's hanfu have different styles:

• Shenyi, means "deep garment" literally, is a belted floor-length robe with wide sleeves. Just as its name implies, shenyi wraps the body deep within it.
• Shanku, refers to a two-piece set hanfu. It composed of a regular or knee-length jacket("shan" in Chinese) and a pair of trousers("ku" in Chinese).

Shenyi and shanku are the main styles of hanfu, while beizi and banbi are some optional garments:

• Beizi, also known as chuozi, is a knee-length coat with loose&long sleeves.
• Banbi, a half-sleeved waistcoat.

Those optional garments make the clothing more formal.

Whatever it is shenyi or shanku, the upper garment of them must follows the "jiaoling youren" style&principle, which means if the collar is crossing, you can only have the left side covered the right side. Optional garments like beizi and banbi don't have crossing collar, so they don't follow that principle.