>>11915The short of it is that compilers are stored in memory as a series of voltages representing machine code for your particular CPU architecture. CPUs interpret this series of voltages as instructions for going and performing operations on other series of voltages in memory e.g. your source files.
There's no different "types" of voltages, only different arrangements of the same voltage values (I think 1.5 V for binary 1, 0 V for binary 0, not sure though).
The key thing that I wish someone had told me when starting out is that the buck ends with the CPU and its instruction set (a bunch of commands that the CPU understands natively because it has been physically wired to be able to do so). Once you get to this level it's all logic gates and circuits just doing what they do.