A normal programm is seperated in differente sections (if it is compiled with a compiler, if we write assembly we need to seperate our sections manually with the section directive).

These sections are text, bss, and data.

Section	Descritpion
text	Here the code of a program is stored. In a more advanced process loader that can load elf files this sections should be read only, because the process should not be able to modify its own code while running.
bss	In this section are global and static variables placed which dont have a value at compile time
data	In this section are global and static variables placed which have a value at compile time

Remeber: Variables that are defined in the scope of a function are placed on the stack (if they are not static lel)