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The Origins of Xcode 4

Xcode 4 has its roots in Project Builder and Interface Builder, the two development tools created for NeXTSTEP. The NeXTSTEP operating system ran on the NeXT computer, which was manufactured by NeXT, the company Steve Jobs founded when he left Apple in 1985. The hardware side of the business was not successful and NeXTSTEP morphed into OPENSTEP, which ran on Sun’s Solaris operating system, and later on Windows. After Apple purchased NeXT in 1996, the software became Rhapsody and, later, Mac OS X. A branch of the software became the iPhone operating system which, after the introduction of iPad, became iOS.

Project Builder and Interface Builder remained the developer tools through all this time. Project Builder was the tool you used to write code, and Interface Builder was the graphically oriented tool you used to draw the interface. Project Builder was renamed Xcode in 2003; it contained significant changes to its user interface at that time.