Personally, I haven't implemented this though I know I should... but I came across this idea in Robert Heinleins Double Star as a reference to Farley Files.
In essence, Farley was Roosevelts aid and kept files on everyone he met so before meeting them again Roosevelt could cram study and "recall everything about them" like they were a close personal friend.
In essence, Farley was Roosevelts aid and kept files on everyone he met so before meeting them again Roosevelt could cram study and "recall everything about them" like they were a close personal friend.
https://en.wikipedia.org/wiki/Farley_file
For some reason this is how I think of Google/FB/et al keeping info on people.