This may help explain it, OG.
"RAM or "Random Access Memory," is the special memory where the data is stored temporarily. The user’s photos, apps, and videos are kept in the internal storage permanently, but when these files are requested by the user it is the RAM that goes into action. After the power is turned off on the device, what is stored in the RAM is deleted...........
The internal memory is where the apps, documents, and other files can be stored and is different than RAM..........For example, some models of the Galaxy tablets claim to have 16GB of storage, but actually they have 12 GB of usable storage..... For instance a 16GB tablet can store approximately 9,000 photos, 3,500 songs, or 20 hours of video......"
http://www.ebay.com/gds/How-Much-Memory-Should-My-Tablet-Have-/10000000177629447/g.html