What do you understand by simple harmonic motion?

Is the motion of a mass on a spring when it is subject to the linear elastic restoring force given by Hooke's Law. The motion is sinusoidal in time and demonstrates a single resonant frequency. There are different equation to take into account:

y=Asin(wt)

T=1/f

f=w/2pi

w=sqrt(k/m)

where A is the amplitude; T is the period; f is frequency; w is the angular frequency; the k is a constant and m is the mass.