Decaf

Decaf is short for decaffeinated coffee. It’s coffee from coffee beans that have had at least 97% of their caffeine removed.
Caffeine can also be removed using carbon dioxide or a charcoal filter — a method known as the Swiss Water Process.
The beans are decaffeinated before they’re roasted and ground. The nutritional value of decaf coffee should be almost identical to regular coffee, apart from the caffeine content.
However, the taste and smell may become a little milder, and the colour may change, depending on the method used.