IBM i (OS/400) the Database Operating System

IBM i (formerly AS/400) is a unique operating system developed in the 1980s that merged the advanced technology of IBM's System/38 with the user-friendliness of the System/36. Unlike Windows or Linux, IBM i has its relational database (Db2) built directly into the kernel rather than as a separate application, making it an inseparable operating system-database unit that handles security, memory management, and record locking at the most efficient level. This revolutionary architecture, designed by Dr. Frank Soltis, has enabled exceptional backward compatibility for decades—allowing programs written in 1990 to run natively on current systems—and made IBM i dominant in online transaction processing.