What is the second law of thermodynamics, in terms of heat/energy

The second law of thermodynamics says that processes that involve the transfer or conversation of heat energy are irreversible. The second law also states that there is a natural tendency of any isolated system to degenerate into a more disordered state. One thing the second law explains is that it is impossible to convert hear energy to mechanical energy with 100 percent efficiency.

Hairy thick gross thing? idk