Memory is a story we tell ourselves about the past, and the memory is recreated every time we tell the story. It's very possible to have real memories of things

Memory is a story we tell ourselves about the past, and the memory is recreated every time we tell the story. It's very possible to have real memories of things that never happened. We can make them entirely on our own, or people can put them into our heads. Real memories of things that never happened. Dr Julia Shaw's "The Memory Illusion" contains a readable account of doing so.