Final answer:
The company that produced the System/360 mainframe computers is IBM. The System/360 was a family of 19 compatible computers that introduced the concept of compatibility in computing.
Step-by-step explanation:
The company that produced the System/360, a family of 19 compatible mainframe computers, is IBM. The System/360 was introduced by IBM in 1964 and was a groundbreaking development in the field of computing. It introduced the concept of compatibility, meaning that software written for one member of the family could run on any other member, which was a major advancement at the time. The System/360 was widely used in business and government sectors and is considered one of the most successful computer systems ever developed.