Hi Can someone help Me with this Please... Beat Frequency Question

[nutrinoland]

So in this article

http://hyperphysics.phy-astr.gsu.edu...subton.html#c2


it says that any 2 tones of different frequencies, will interact and produce a third , beat frequency, which is the difference between the two frequencies. Also harmonics within one Tone, such as a saw wave, interact to re-enforce the fundamental frequency, as the difference between the successive harmonics is equal to the Fundamental frequency.
SO WHat would happen to a Square wave though, which has a series of Odd Harmonics ? would it not start to become a Saw wave as its harmonics, created a beat frequency not equal to the Fundamental ? also as the different harmonics (sine waves) interact with each other, wouldn't We have beat frequencies at the full harmonic series ?..A saw Wave ... right ? Yet That is not what happens...cause clearly its still a square wave... ?? whats going on ?
PLs read the article to better understand My question.

Thanks