Hi
i have a i686
at least my computer says so after echo $HOSTTYPE

I am using Fedora i386 on this machine.

Will it damage my computer?

What happens if i install x86_64?

Better read this (and alike) first:
http://en.wikipedia.org/wiki/I686

x86_64 means a 64-bit distribution that will only install and run on a 64-bit machine (you know, some cpus sold nowadays are 64-bit, most are 32-bit). Among 32-bit machines there are various flavours, that are marked with i*86 (i386, 486, 586, 686). It won't hurt your machine to run a "i386 Fedora", though your 'uname -a' states your machine is "i686" Read more about this at Wikipedia (or any other website) and it'll become more clear to you. Shortly said, almost every pc can run i386-marked software, but only some (new enough) can run i686 for example.

If something might hurt your machine, you would probably be informed about it.

I suspect that Fedora will have installed a 686 kernel instead of a 386. Just run uname -m to find out.

Ty for ur replies
uname -a and uname -m are OK

i used to use

echo $HOSTTYPE