" is it possible for me to install any version of Linux operating system on it. "
Not all versions can install to external USB drives. Even fewer machines can boot from USB drives.
You'll have to experiment a little. In closing, it's very slow, even at USB 2.0 speeds.
Bob
I've wondered that if I had purchased an EXTERNAL hard drive, not an internal one, is it possible for me to install any version of Linux operating system on it. What I plan on doing, instead of partitioning my existing 40 GB hard drive, I may keep Windows XP on that one, and just get like another 80 GB hard drive soley for Linux. But since it is recognized as a USB, is it possible for me to not only install Linux on it, but boot from it as well.

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