Bennett's laws

Bennett's laws of quantum information are:
 * 1) 1 qubit $$\geqslant$$ 1 bit (classical),
 * 2) 1 qubit $$\geqslant$$ 1 ebit (entanglement bit),
 * 3) 1 ebit + 1 qubit $$\geqslant$$ 2 bits (i.e. superdense coding),
 * 4) 1 ebit + 2 bits $$\geqslant$$ 1 qubit (i.e. quantum teleportation),

where $$\geqslant$$ indicates "can do the job of".

These principles were formulated around 1993 by Charles H. Bennett.