Some people remember almost every single day of their life in detail
People with Highly Superior Autobiographical Memory can be given almost any date and recall what happened, what day of the week it was, often even the weather — with no mnemonic training. The first confirmed case, a woman known in research as 'AJ,' was studied from 2000 onward. Brain scans show structural differences in their memory circuits, but why the ability appears is still unclear.