Virtual Memory Optimization Guide Part 2
 

Back in the 'good old days' of command prompts and 1.2MB floppy disks, programs needed very little RAM to run because the main (and almost universal) operating system was Microsoft DOS and its memory footprint was small. That was truly fortunate because RAM at that time was horrendously expensive. Although it may seem ludicrous, 4MB of RAM was considered then to be an incredible amount of memory.

However when Windows became more and more popular, 4MB was just not enough. Due to its GUI (Graphical User Interface), it had a larger memory footprint than DOS. Thus, more RAM was needed

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