BitLocker ?

Hi , Can someone please explain how to use this program ? I try it once on my drive and it created another smaill drive . why ? Even though now I reformated my computer back to original way it was before this . I am now curious as to what this program does and how to use it ?

Thank you

That will explain better than i could do
BitLocker Drive Encryption - Wikipedia, the free encyclopedia

I have a faint idea as to what it is but I am not sure really how its use . When I did try it I got this report afterward below . I am not sure what to do here or better yet what is TPM ?

A TPM was not found . A TPM is required to turn on BitLocker . If your computer has a TPM , then contact the computer manufacturer for Bitlocker-compatible BIOS

And all my Volumes are set on Off

Thanks

A TPM is a microchip providing basic security-related functions. The TPM is usually installed on the motherboard of a machine, and communicates with the system using a hardware bus.
So check your BIOS if it is compatible with TPM. I know that Bitlocker can eventually work without TPM but i do not remember exactly how to configure the drives to make it work

Hi, I don't believe my board does , though i am looking into booting from a usb flash stick and taken it maybe that route , If it does then I will need to learn how its done . I know my board bios screen show removeable dev. As to what really that does I am now looking at the manufacturer for the answer . So i'm crossing my fingers lol .

Walkthrough on how to install bitlocker with usb key(without TPM):
How To Enable Vista's Bitlocker Encryption without a Trusted Platform Module (TPM) chip | eHow.com

Walkthrough on How to remove bitlocker and repair boot manager( if it wont encrypt drive, or you decide you no longer want it):
How to Remove Bitlocker and Repair Boot Manager