9 Computer software for data storage, data searching and data reduction, namely, computer software for identifying new or different data, similarity searching, pattern recognition, eliminating data redundancy, creating and/or maintaining a data repository, providing reduced bandwidth data transmission over a network, and operating back-up and restore systems. Computer software for data protection, data back-up and recovery, and data storage regulatory compliance, namely, computer software for simulating tape storage devices with virtual tape devices and data stored on disk