Baud reat means how much the the signal is changed from logic high to logic low
in one second
e.g when we say baud rate = 1000 thats mean the signal is changed from high to low 1000 time in the second
regards
Sampling rate, refer to the serial receiver clock, that sample the incoming signal in order to decide when a transition, in the incoming stream, occured. Usually, it's 8 to 16 times higher then the baud rate.