Separation of function by region

The memory allocated to each process is split into regions based on the function for which each region is used. The three regions are:

code or text

Text regions are usually shared between multiple processes that are executing the same program code and are not writable. Any attempt to write to an address within a text region produces a run-time error that results in a core dump.

data

The data region is a writable region that contains the initialized data segment from the program code plus the uninitialized data segment (or bss segment) allocated when the program is loaded. Any process that attempts to execute at an address with the data region will dump core.

stack

The stack region contains the process's stack only. Like the data region, it cannot be executed.