Hi, so i have an iMac and all the rest but i was looking into the macbook airs, i see the cheapest one has a '64GB flash drive'... so tell me whats the different between SSD and a flash drive .. or are they the same? Also my iMac has a 1TB HDD and then looking at something thats 64gb i mean .. i have seen the speed on youtube and they are mega fast but what does everyone do to store files because 64gb isnt really enough? Thanks. Can someone explain what a 'flash drive' really is? thanks.