Quite different from what you can do with a piano - where you have only one dimension in creating a tone, and that is the speed with which you press down the key, which translates directly into volume (despite what your piano teacher might have told you) the clarinet has far more options to create a tone. One very important is the the attack. We have already heard of it in the paragraph above: "TAAA", "DAAA" and, off course, "HAAA". The latter would be a tone without real attack. And then there is legato, which means there is no break in between two tones at all, that is, the vibrating air column vibrates on theoretically. (It is theoretically only because the vibration is in fact interrupted for a short moment; although you may not notice that so obviously.