Apple Developer

Apple Developer, formerly Apple Developer Connection or ADC, is Apple Inc.'s developer network. It is designed to make available resources to help software developers write software for the Mac OS X and iOS platforms.

There have been several leaks of secret Apple software through the prerelease program, most notably the Mac OS X 10.4 Tiger leaks, in which Apple sued three men who allegedly leaked Mac OS X 10.4 prerelease builds to .

OS X Lion, OS X Mountain Lion, and OS X Mavericks, were leaked several times as well. However, to combat this issue Apple installed an alert system in the preview builds, alerting them if they had been uploaded by a tester to a system.

On July 18, 2013, an intruder attempted to access sensitive personal information on Apple's developer servers. The information was encrypted, but Apple could not guarantee that some information about developers may have been accessed. The Developer website was taken down for "maintenance" that Thursday, and was said to be undergoing maintenance through Sunday, when Apple posted a notice on the site notifying users of the attempted hack. They have stated that they will be re-building their servers and the developer system to prevent this from happening in the future.

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Wikipedia