Hi, I have FreeBSD 6.0 and Slacware 12 DVD's and have no spare partitions on my Windows PC or my Apple and don't want to reformat them. So the question is is it possible to install linux on an external HDD? or partition a HD in a new computer, say 60GB for linux and the rest for Windows or OSX. Please advise.

Yes, lots of people have done it. Keep in mind, where ever you decide to install a linux system, you will need a boot loader, and its placement can cause problems for other OS's.

The most common place to put it is the master boot record of the first disk. There are two boot loaders commonly used in linux, lilo and grub. I would recommend you use grub, it is the newer one, and is more flexible. You need to do some research, and understand the effect of putting a boot loader on the mbr on all installed OS's.

Yes this will work also. Install any winbloze systems first. Don't invest time in winbloze until you do your linux install. As stated above, you need a boot loader. Some of the distros will detect a windoze install, let you write grub to the mbr, and update the mbr so you have an entry for any other system installed.

Just so you understand, the bios sends the heads on your hard drive to read the mbr. On a windoze system it would find a record to send the heads to start loading windoze system files. With grub on the mbr, grub will give you a menu to select which OS you want to boot. You make a selection, and the heads are sent to the appropriate partition for that OS.

I would say all of the above is possible, the easiest being partitioning your original hd (if it has plenty of room) and installing all on one drive. This can be done without any damage to windows if you follow a couple of steps. There are a lot of articles here and on Google on everything you have mentioned above. The main two steps I have always taken was to defrag windows first and then partition the hd and leave at least 50% to the windows domain.

RE:Yes, lots of people have done it. Keep in mind, where ever you decide to install a linux system, you will need a boot loader, and its placement can cause problems for other OS's. The first thing I will consider is installing it on an external HD. When it's on cfdisk doesn't detrect it. Will fdisk, if so how do I get it to. As far as I know windows will not install an OS on an external HD and linux needs windows boot loader and mbr to install. Question, As you can install OS's on external HD connected to a MAC is it possible to use linux on a MAC, I won;t dare try though.

One weekend' work to put 12 systems into a USB external hard disk. There is a BSD there as well.

My preference with two internal drives is to install windows on the master, then change this to the slave. Now install linux on the new master, leaving the win drive alone. You can find a ton of documentation on the 'net as far as the configuration of the linux bootloader (lilo or grub) to make this work.