1. PC
1.1. Unix like
1.1.1. Linux
1.1.1.1. C, Assembly
1.1.1.2. open source
1.1.1.3. Linus Torvalds, Red Hat, Debian Project
1.1.1.4. x86-64, ARM, PowerPC, SPARC
1.1.2. OSX
1.1.2.1. C, C++, Objective C
1.1.2.2. closed source
1.1.2.3. Apple Inc.
1.1.2.4. PowerPC, x86-64, ARM
1.2. Windows
1.2.1. C, C++, Assembly
1.2.2. closed source
1.2.3. Microsoft Corporation
1.2.4. Itanium, x86-64, ARM, MIPS, PowerPC
2. Mobile
2.1. BlackBerry
2.1.1. C++
2.1.2. closed source
2.1.3. BlackBerry Ltd.
2.1.4. BlackBerry lines of smartphones
2.2. Windows phone
2.2.1. C, C++
2.2.2. closed source
2.2.3. Microsoft Corporarion
2.2.4. ARMv7
2.3. Android
2.3.1. C, C++, Java
2.3.2. open source
2.3.3. Android, Inc., Google
2.3.4. ARM, MIPS, MIPS 64, x86-64
2.4. iOS
2.4.1. C, C++, Swift, Object C
2.4.2. closed sorce
2.4.3. Apple Inc.
2.4.4. ARMv6, 7, 8
3. Server
3.1. FreeBSD
3.1.1. C
3.1.2. open source
3.1.3. The Free BSD Project
3.1.4. IA 32-64, x86-64, SPARC64, MIPS, PowerPC
3.2. Windows Server
3.2.1. C++
3.2.2. closed source
3.2.3. MIcrosoft Corporation
3.2.4. x64
3.3. Linux
3.3.1. C
3.3.2. open/closed source
3.3.3. Linus Torvalds, Red Hat, Debian Project
3.3.4. x86-64, ARM, PowerPC, SPARC