Makefile is a file used by GNU make where dependency relationship are listed. Variable are used to avoid repeation (because coder are lazy).
There are two types of action :
- A
Creation / Updatingaction. - A
phonyaction.
You can find a complete guide here
Those actions just creat or update the file asked.
exemple : make greeting or make farewell_dir/objects/say_goodbye.o
Those actions just do something, without creating any file.
exemple : make clean