The Apple had the ability to show different regions of memory.

A pixmap is a region of memory that can be used for drawing.

There were two pages of and regions of memory in the old PC.

So that two threads might both say I need exclusive access to this region of memory.

Each process has access to three independently extensible regions of memory, used typically for program, heap and stack.

This region of memory is not to be modified by interrupt/exception/signal handlers.

Applications could first request a region of memory outside the current display region for use as bitmap.

Data to be written or read is put into a special region of reusable memory referred to as a buffer.

Instead, it is usually a region of memory that's aligned on a 4KB boundary.

In most modern computer systems, each thread has a reserved region of memory referred to as its stack.