BitLocker was Microsofts first transfer to full disk file encryption with support included in Windows Vista. Since then BitLocker has evolved and enhanced into a great softwarebased full disk file encryption resolution. New for Windows 7 is support for removable disks. By means of BitLocker on a removable USB flash drive gives a good way to defend your computer data in the event the drive was missing or thieved.
Not only will your data always be protected but it is
possible to gain access to your computer data on Windows XP and Vista
using a read-only interface that's installed during the initial
encryption. Now you are able to get your data anywhere, not just on your
Windows 7 computer.
how to encrypt the removable USB flash drive with Bitlocker?
1: Insert your USB flash drive and open Computer so you can
view all your drives. Then, right click on your drive and select Turn on
Step 2: Select the way that you want
to protect the drive. There are 2 options for you to protect your USB
flash drive: using a password to unlock the usb or use the smart card.
3: Click Next to continue. In case of the password lost or
forgotten, just backup your recovery key so that you can always retrieve
Step 4: Click Next to continue and then
click Start Encrypting. Your drive is now protected when the encryption
Additional knowledge, with a USB flash drive, you can
not only take it for keeping your data in a safe place, it can also help
you to create a password reset disk to unlock the password if you forgot
Windows 7 password or even need to solve your Windows 8 password recovery issues.
Article resource from: http://www.passworddecrypt.com/how-to-encrypt-removable-usb-flash-drives-with-bitlocker/