When it comes to reading, we first learn letters, then we learn how to read syllables, words, sentences, paragraphs, chapters, and eventually whole books. The same principle applies to writing and just about any other fundamental skill. Once it comes to memory - we do not learn the actual process. Our far from perfect educational system expects us to remember significant amounts of information without teaching us how to memorize it in the first place. Its like throwing kids into the middle of the ocean without teaching them how to swim beforehand. Nor providing them with a boat.
