Track Pants- These are sweatpants, but fashion. Wear your baggy cotton sweatpants to the gym, wear your fitted and fly track pants on a casual outing. For extra credit, get a pair in cashmere.
Corduroy Pants- The perfectly warm cold weather pants that can be worn casual or dressed up for work.
Chino Pants- Another versatile pant that can be dressed up or down.
Wool Pants- These are your dress pants for work. You can also wear the pair that came with you suit without the jacket.
Jeans- These are probably the pants you’re going to wear the most, so get several colors including a light, medium, and dark wash and a pair in white, black and grey. A camel colored pair is also really versatile. For a complete denim buying guide, read this.