The main difference in the various types of fit is the amount of fabric used in the clothing. The slim fit fits the body closely and comfortably. It is a good choice for men whose body type is lean and slim, with narrower shoulders and chest. It’s snug through the shoulders, chest, arms and thighs. Jackets and shirts are fitted through the waist while trousers are neat through the seat and taper towards the ankle to skim the top of your shoe.
For many brands, the slim fit is usually the tightest fit available and offers little allowance for tailoring down.