Having a all memory computer was always the goal, even back in the 1960's.
The cost per bit has been the driver. Floppy disks, hard driveds CD-Roms, DVD's, and now the solid state memory devices are just a life cycle of devices aimed at the same purpose.
Lots of storage in a small space.
I remember when IBM boasted that magnetic "bubble" memory would take the world storage market. Its brief history as a product shows how fast technology rises to replace one implementation with a better one.
So SSD's are todays best implementation, anyone want to speculate what the next one will be?
You just have to love technology. It changes every day.
