Kombucha is commonly known as a fermented, slightly alcoholic, lightly effervescent, sweetened black or green tea drink. How kombucha came to mean black/green tea has been lost in translation. Real kombucha is made from seaweed.
In Japanese, Cha (茶) means tea, and kombu means brown seaweed (kelp), therefore kombucha is kelp tea!
Below is a video showing how real kombucha is made.