Unless it specifically states "caffeine-free" on the label, YES. Chai tea is made with black tea as a base, with spices and flavourings added. Black tea has caffeine in it. Decaffeinated teas have...
Yes, it does. Caffeine is caffeine.
Caffeine exists in many places in nature particularly tea and coffee.
Caffeine is a stimulant that temporarily reduce the sensation of being tired. Extreme amounts of caffeine can cause health problems.
Yes - If something contains no caffeine, it can also be classified as being 'caffeine free'.