A "hackbook" is a non-Apple laptop running an unauthorized version of the macOS operating system. The name comes from the combination of "hack" and "MacBook" (Apple's name for their line of laptops).
Apple prohibits users from running any version of macOS, or Mac OS, on a non-Apple piece of hardware in their end-user license agreement. However, some users who want to use a Mac operating system on laptops still hack the software and hardware to make hackbooks. These users may find MacBooks too expensive or prefer non-Apple laptops, typically PCs.
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