ooh i wish keith were here...
ill try my best here and maybe someone can help me out
ram (standing for random access memory) is a memory that you read and write numbers to. it is erased every time you disconnect power for about 10-15 secs (or however long it takes power to discharge from the circuit). when you download code into the robot it is stored into whats known as eeprom which is a type of memory that doesnt get changed until someone goes in and changes it (ie downloading new code). the scratchpad ram is what is used when you are trying to save a temporary value that will be changed at different points in the code (aka a variable). you have 62 scratchpad ram locations total in each bank.
to sum this all up...
scratchpad ram is the physical memory area inside the robot controller where all your variable values are stored.
hope that helps
(dont feel sad for not knowing... i dont know a lot of things and im about 1/3 of my programming team) (well maybe 1/4... keith is probably 1/2 of our team
)