An
FTP install is when you
install something by
downloading a
small installer, which then
FTP's the
rest of the
product over to your
computer.
This is both good and bad.
It is a Good Thing because A) it uses the internet, meaning you always get the most recent version, and you don't have to carry a install CD around, and B) it only downloads what you need it to do. This can be very efficient.
It is a Bad Thing because A) it uses the internet, which means that if the server goes down, you are screwed, and that if the internet is slow today, the install takes forever, and B) it only downloads what you need it to - and if you do a full install, that means _everything_.
But I think it is overall a more good than bad thing, because the only OS I have seen which supports this is Linux, and I love the feature. Netscape 6 also uses this. I dislike it, because it means I have to redownload the install files every time I install it. I wish they had, as an option, a standalone installer.