From the information theory angle, there is no difference. In practice, there is. There is a difference between something-you-have secrets and something-you-k

From the information theory angle, there is no difference. In practice, there is. There is a difference between something-you-have secrets and something-you-know secrets. A UrL is something you have. It can be taken from you if you leave it somewhere accessible. Passwords are something-you-know and if managed well can not be taken (except for the lead pipe attack). There is also something-you-are, which includes retina and fingerprint scans.