What are the different types of tea, and why you should try them?

Tea soup of balck tea is red, and oonlong is yellow.Tea leave of black one is black, while oolong can be dark green.

Black tea is a fully oxidized tea(amount of oxidation changes certain elements of the tea: taste, color, etc.), which is why it is so dark. Oolongs are oxidized at levels in between black and green (not oxidized). Hope this helps!