What is noise margin and noise immunity?

Noise margin refers to the difference between the actual voltage levels of a digital signal and the threshold levels required for reliable recognition of logic states, providing a buffer against noise interference. Noise immunity, on the other hand, is the ability of a system to withstand external noise without affecting its performance or accuracy. Together, they are crucial in ensuring reliable digital communication and signal integrity in electronic circuits, especially in environments with potential electromagnetic interference. High noise margins and strong noise immunity enhance a system's robustness against disturbances.