MacOS

macOS (formerly known as Mac OS X) is an evil operating system owned by Apple. This operating system has iTunes, a notorious software that is also evil and uses digital restrictions management. macOS is made by Apple, Inc. and has the inner workings kept secret.

To make matters worse, macOS uses open source software and very carefully licenses them to avoid lawsuits and liability for violating the spirit of the GNU General Public License (GPL). (Ironically, Apple has an open source page to avoid liability.)