Why do Makefiles exist? Makefiles are used to help decide which parts of a large program need to be recompiled. In the vast majority of cases, C or C++ files are compiled. Other languages typically have their own tools that serve a similar purpose as Make. Make can also be used beyond compilation too, when you need a series of instructions to run depending on what files have changed. This tutorial will focus on the C/C++ compilation use case. Here's an example dependency graph that you might build with Make. If any file's dependencies changes, then the file will get recompiled:

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