Could anybody explain the difference between magnetic induction and RF?

Obviously there is inductive charging with two coupled coils, used as=20
for charging small devices.  However my confusion comes from this part=20
of a manual for transponder based timing:

"Since the AMB transponders operate on magnetic induction, they have no
antenna but a built-in coil instead. The transponders do not produce an
electromagnetic (radio) wave but only a magnetic wave. The difference
between an electromagnetic (radio) wave and a magnetic wave is that the
electromagnetic wave travels by itself over great distances and the=20
magnetic wave does not." [1]

I don't understand this difference, the transponders use a fixed=20
frequency (near 4Mhz) and digital modulation.  They probably use a=20
ferrite rod, but I am unsure how this is anything other than very low=20
power RF.

My interest comes as I'm trying to improve a simple transponder based=20
system that I designed last year, and want to know if there is some=20
magic that I am missing.

Thanks,

David

1 - http://tinyurl.com/dypszke (Appendix G)
--=20
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