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Vista's DRM technologies fall into several distinct categories, all of which are either completely new to the operating system or represent a significant change from the technology found in previous versions of Windows. The Intel-developed Trusted Platform Module (TPM) makes DRM harder to circumvent by extending it beyond the operating system and into the PC's hardware components. TPM is used with Vista's BitLocker full-drive encryption technology to protect a PC's data against security breaches. A TPM microchip embedded on the PC's motherboard stores unique system identifiers along with the BitLocker decryption keys. If a system is tampered with -- for example, if the hard drive is removed and placed in a different machine -- TPM detects the tampering and prevents the drive from being unencrypted.