sampling theorem is defined as , the sampling frequency should be greater than or equal to 2*maximum frequency, and the frequency should be bounded..

i,e

fs=2*fmax

where fs= sampling frequency

Not less than double the highest frequency component of the signal you're sampling.

A: A sampling scope is not real time scope but rather a hi frequency rate of sampling which benefit the observer

The Nyquist Theorem says that the sampling frequency should be twice the bandwidth to avoid aliasing. Thus if the bandwidth of the system is bw then the sampling frequency f=2*bw.

frequency is simply the rate at which something is happening, ie the frequency of Christmas is once a year, the frequency of having breakfast is once a day etc. If frequency is expressed in Hertz, it's how many times something happens during a second.

Sampling is, well, sampling. Usually means testing and measuring something changeable. If you're running a bath and occasionally stick your fingers in to check the temperature, then that's sampling,

Sampling frequency simply describes at which rate you're making whatever test or measurement it is you're talking about.