what type of files are compiler programs

[BRMV]

Hi,

In program execution process the sourece code undergoes through preprocessor , compiler ,assembler, linker, loader and finally the executable file will be generated.

what type of files actually are these (preprocessor , compiler ,assembler, linker, loader) and at which stage does the memory is allocated to variables.
I am interested to know in detail about these.

thank you.

[Gaminic]

I doubt any memory is allocated until the program is actually executed.