Kathmandu
Kathmandu is the capital and largest city in the country of Nepal. It forms one large urban area that includes the area of Patan to the south. It is likely to be your entry point into Nepal and is a great place to pick up supplies and arrange the details for any treks you hope to do. Specifically, in the Thamel Chowk neigborhood you'll find no shortage of equipment shops, food stores, and hotels. In this neighborhood you'll find the highest concentration of travels either beginning, or just finishing their treks. If you're hoping to pick up some equipment, keep in mind that most of the supplies are knock offs, and the quality is variable. Negotiate hard, and if you're purchasing an authentic item, you are likely to pay full price for it, a price that is comparable to what you would be in a western country.
Many travelers rush through Kathmandu, turned off by pollution and crowds, but to skip Kathmandu is to miss a major cultural, financial, and influential part of what defines the country of Nepal. The city itself is quite fun to explore if you allow it enough time and an open mind. Be sure and visit Swayambhu, a large stupa and sacred Buddhist spot. Also go to Boudha Stupa, Narayanhiti Palace Museum, and Freak Street. Durbar Square is an absolute must see, and is best visited in the early morning or evening.
Restaurants in Kathmandu are quite good. You'll find the highest concentration of restaurants that cater to tourists in the Thamel neighborhood. You can find plenty of Nepalese food, in particular, momos, which are a great late night snack. Nepalese food is quite similar to Indian food with subtle differences and some Chinese influence. You'll also find plenty of Thai, Chinese, and dessert options throughout the Thamel area.
To get out of Kathmandu there are a couple of bus stations to choose from. Make sure you fully understand which bus station you need to go to to catch a bus headed to your intended destination. The process can be somewhat confusing.