spyware on macs ?

hi - i've been a long time windows user but b/c of all the spyware ***
that happens in internet explorer and even seems to happen on firefox -
i'm pissed enough that i may buy an apple. anyways a few questions:
why the *** to the O/S makers ( microsoft and whoever else ) allow
this spyware *** on the operating system or in the browser ???
does apple allow this spyware *** in it's O/S or browsers ?
are the o/s companies doing anything about it ???

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