Question: Is it illegal for Apple OS to reuse code written for the Windows operating system?, Answer:Yes, Description of MacOS: Operating system for Apple computers, Fact1: Code written for the Windows operating system is proprietary, not open source., Fact2: It's illegal to use proprietary code unless the creator agrees to license it to you., Fact3: Microsoft refuses to license Windows code to Apple because they're competitors.
Step1: Propriety code is is a closed source software which is not free to use., Step2: Windows operating system is a propriety graphical operating system developed and marketed by windows., Step3: Apple OS is the operating system developed and marketed by Apple., Step4: Is it illegal for #3 to use #2 because it is #1?, Wikipedia page for step 1: https://en.wikipedia.org/wiki/Proprietary_software, Wikipedia page for step 2: https://en.wikipedia.org/wiki/Microsoft_Windows, Wikipedia page for step 3: https://en.wikipedia.org/wiki/List_of_Apple_operating_systems#Classic_Mac_OS, Wikipedia page for step 4: , not_definitive_answer: False, incorrect_answer: False