Simply put, Chai tea is flavored tea.

here is a thread where alpinerrabbit and I wrote our recipe for our chai. chai thread

I've been tweaking my recipe for some time. It's definitely much cheaper to make your own. I've gotten bit lazy so I make my mix in bulk now. Each tablespoon of the mix makes about 750ml (3 cups) of tea. Cost is around $2.00 per gallon for the tea maybe?? And my tea is pretty strong so I mix 1/4 to 1/3 tea to 3/4 to 2/3 non-fat milk. Lots of honey. yummm...

I have my standard spicy chai and my second one is vanilla flavored. Still working out on orange spice chai. It came out like orange pekoe tea (not good).

I have four other flavors I'm thinking about. Pumpkin wasn't one of them. pumpkin spice sounds yummy.