MK is a file extension for a makefile. A makefile is used with the UNIX make utility to determine which portions of a program to compile. Essentially, a makefile is a script that guides make in choosing program files should be be compiled and linked together.
MK files are commonly used with C programming, but can be used with any programming language that can be compiled via a shell command. MK files contain a list of commands involved in updating program files via the relationships described in the makefile.
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