Upon reading Joshua Foer‘s Moonwalking with Einstein, I came to learn that unless you’re a savant like Kim Peek, people have relatively average memories. In the first chapter, Josh explains his experience at the World Memory Championship where he meets legendary mnemonics such as Ed Cooke and Ben Pridmore. According to the champions, memory retention is all about technique and not an extraordinary innate ability.
In later chapters, Joshua explains through narrative and participatory journalism the art of remembering everything through techniques such as the POA System and the Major System. Both of these systems use a millennia old technique called a Memory Palace whereby you walk through your house, place of work, cottage, etc. and drop the most colourful, crude, multi-sensory cues throughout the place in order to recall them, in that order, later on.
After reading about the Memory Palace, I used it to memorize a 20 item grocery list in less than 10 minutes. I couldn’t believe how effectively it worked.
Authour Joshua Foer has also presented a Ted Talk on the subject which i’d suggest you check out.