Live CDs need no introduction. and neither does Knoppix, probably the first live Linux distribution. Live CDs
are great as they let you run an entire Op¬erating System directly from a CD on any machine without tampering with your ex¬isting system settings. However, the draw¬back is that CDs and DVDs are read-only. So you can't really write data on a live CD or DVD. So if you want to carry your OS around with you, and be able to store and change your documents in it. the CDs and DVDs just won't do. You need something with read/write capabilities. That's where flash drives come in. and in this article, we'll tell you how to have your own Linux distro complete with all the apps you need on a USB-based flash drive.
We have used a Knoppix 5.1 ISO on a USB drive, but ideally this process should work with any Live distro that uses Isolinux for booting.

Prerequisites
Get a hold of any 1 GB USB flash drive. Download the ISO of Knoppix 5.1 from knop¬pix/KNOPPIX_ V5.1.1CD-2007-01-04¬EN.iso. You will also require a tool called 'fixkp.bat' that will extract and modify the Knoppix ISO to run from the USB drive. This can be downloaded from Creating a bootable USB Create a new folder named USB Knoppix anywhere on your computer. Let's assume that you created it at C:\. Move the Knoppix Linux ISO to this folder and then ex¬tract fixkp.zip into the same folder. Since fixkp.bat is a simple batch file, simply run it from a command prompt. It will extract the Knoppix ISO in the C:\Knoppix folder and modify it to run from the USB drive. This process will take around a minute and it will automatically create a new folder named 'knoppix' in the C:\Knoppix folder.
Now format your USB drive with FAT32 file system. Then copy all the con¬tents from the 'C:\Knoppix\knoppix' folder to your USB drive. Now go to the command prompt and change the location to your USB drive. Let's assume it's E. From here, simply run the makeboot.bat batch file. That's it. Your live USB drive is ready.

Reboot your PC and enter your BIOS setup. Change the first boot device to USB drive and reboot. This time when your PC boots up, you should see the Knoppix boot screen. Pressing enter will start Knoppix. If you are using a USB 2.0 port, then it will be much faster. You can use this drive from any PC or laptop. Just make the first boot device as the USB drive.