Brad J. Cox (born 1944) was an American computer scientist who, with Tom Love, created Objective-C in the early 1980s. Working at their company Productivity Products International (later Stepstone), the two set out to bring the object-oriented model of Smalltalk to the practical, widely deployed world of C. The result was a hybrid: a strict superset of C with a Smalltalk-style message-passing object system layered on top, so that programs could run with the efficiency of C while gaining the abstraction and reuse of Smalltalk.
Cox set out his thinking in his 1986 book “Object-Oriented Programming: An Evolutionary Approach,” published by Addison-Wesley and now preserved on the Internet Archive. The book is both a tutorial on Objective-C and a manifesto. Its central argument, as the Computer History Museum summarizes, was that “object-oriented programming could be used to create libraries of software objects that developers could then buy off-the-shelf and then easily combine, like a Lego set, to create programs in a fraction of the time.”
That idea of the reusable “Software-IC,” an analogy to the interchangeable integrated circuits of hardware engineering, was the intellectual core of Cox’s career. He believed the software industry suffered because programs were hand-built each time rather than assembled from tested, packaged components, and he saw object orientation as the path to an engineering discipline of reusable parts. Objective-C’s dynamic runtime and message dispatch were designed to make those components composable at the boundaries.
Objective-C found its lasting home not at Stepstone but at NeXT, which licensed the language and made it the foundation of NeXTSTEP. Through NeXT’s frameworks, and Apple’s later acquisition of NeXT, Objective-C became the primary language of Mac OS X and, after 2007, of the iPhone and the App Store. The off-the-shelf-component world Cox had imagined arrived, in a sense, in the form of Cocoa’s class libraries and, later, the App Store ecosystem itself.
Beyond the language, Cox continued to write about the economics of software reuse and intellectual property, including his later book “Superdistribution.” He taught at George Mason University and remained an advocate for treating software as a manufactured, componentized product. He died in 2021, but the language he co-created powered Apple’s platforms for more than three decades and only began to be displaced by Swift starting in 2014.