Booting from USB
With the BIOS properly configured all that is left to be done is to save the settings and exit. A quick restart and you will be ready to boot from USB. Of course, this is supposing that your USB flash drive already contains the appropriate data.
This part is either very easy or a bit tricky depending on what you need to do. To properly format the USB flash drive you can either use a utility program or use a specialized tool within the software with which you will be booting. Many USB drives will include some sort of software utility which will allow you to format the drive and make it bootable. If your drive did not your drive did include any software HP has a program available which is quite popular. You can find it here. When formatting make sure to use the FAT file system.
If you looking into booting Linux from a USB flash drive there are a few different options, but I have had the highest success rate with Syslinux. This is a lighweight Linux bootloader mainly used for floppy media. This can be useful for distributions of Linux which are tough to get to boot from USB, but some do not need this. Puppy Linux is extremely easy to get to boot from USB and it actually has a built in tool for formatting a USB drive to do this. Other Linux distributions, like Feather Linux and even Fedora Core 3, have been known to work as well.
The quickest way to install Puppy Linux onto a USB drive is to first use it as a Live CD. With is running as a Live CD all you have to do is:
Setup > Install onto a USB stick > (Answer the questions)
After this is over your USB flash drive will be ready to boot Linux onto practically any system. Puppy Linux is the easiest, but the a similar process can be applied to many other distributions.
Booting from your USB stick is quite simple once you know the basics. When you want to start your computer in DOS mode at the A: prompt, boot into Linux, or something more complex, it just takes a little bit of hardware, a few programs, and some patience.