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Version numbers, while in one sense mere labels, carry a message about the magnitude of improvements and changes from one version of software to the next. For that reason, corporate marketing departments often have a hand in choosing them. Sun Microsystems, for example, took its Solaris operating system from 2.5 to 2.6, but when it got to 2.7, it changed its naming convention, labeling the product Solaris 7 to signal it was an important new release.