While Thai food has a reputation for being spicy, Thai food is actually based on a balance between different flavors including spicy, sour, sweet, salty, and bitter. This goes beyond simply combining the flavors within an individual dish to incorporate the contrast in flavors between two or three different dishes, which is one reason Thai’s share meals and eat family style. One distinctive aspect of Thai food is the use of fresh herbs and spices as well as the inclusion of fermented fish sauce in nearly every dish –a potential problem for vegetarians, though saying “jay” to indicate you are vegetarian goes a long way. However, there are certainly regional variations in what is typically considered Thai food; these are due to the influences of neighboring countries, such as China, Laos, Burma, and Malaysia. While some Thai restaurants specialize in specific dishes, most have a huge menu of Thai and western fare and prepare Thai food from throughout the kingdom.
Word of warning, my personal experience has been that if you are with a Thai and you order western style food. Expect to be eating alone as most places I’ve been to they will serve the Thai order before the western food. So site back and enjoy as your Thai friends eat before you.