The release of Half-Life in November 1998 marked a paradigm shift in video game narrative and mechanics. However, beneath the surface of the Black Mesa Research Facility lay a sophisticated software licensing mechanism that would set the standard for PC gaming DRM for half a decade: the 25-digit alphanumeric CD key.
When Sierra Studios first published Half-Life in 1998, digital rights management (DRM) was vastly different from today. Games relied on simple alphanumeric strings to prove ownership during installation. half life 1 cd key 25 digits