Black tea generally should be made with water at a full, rolling boil, 212 degrees.

Oolong tea (also known as wulong tea) should be made with water a little bit below boiling, between 190 and 203 degrees. The water should be steaming rapidly and there should many bubbles rising in the kettle, but not really breaking the surface.

Green teas should be made with slightly cooler water, between 160 and 180 degrees. The steam should be wafting or gently swirling out of the kettle.

White teas should be made with even cooler water, anywhere from 150 to 160 degrees, when you see the very first hint of steam.

Puerh teas are very different, I have had them made with cooler water, similar to a green tea. But my favorite method is to make them with boiling water and steep them a long time.

Herbal teas should typically be made with boiling water.

Different teas also require different steeping times.

Black teas steep 4-6 minutes. Darjeelings are the exception, they should be steeped 2-3 minutes.

Oolong teas (also known as wulong tea) vary dramatically and you need to experiment or follow the suggested steeping instructions on the bag. Many oolongs (wulongs) are perfect at 3-4 minutes, some need 6-8 minutes.

Green teas should typically be steeped for much less time, 2-3 minutes.

Whites teas typically should be steeped around 2 minutes, although some can be steeped much longer with good results.

Puerh teas should be steeped at least 7-8 minutes. I like to steep Puerhs up to 20 minutes.To keep puerh hot, while steeping 20 minutes, simply cover your pot with a
tea cozy or even wrap it with a dish towel. It will stay piping hot.

Herbals typically should be steeped a minimum of 4-6 minutes, some for up to 10 minutes.