system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How exactly does Deja Vu happen, and is it abnormal to experience it daily?

I remember one of my professors giving me this thin, run down explaination of it, but he didnt say more than two sentences. I still don't understand it.
gpt
Humans have two kinds of memory, a short term memory that lasts a few hours and the long term memory that archives the memories. What you perceive from your senses is processed in your short term memory and is eventually shuffled off to long term memory when the brain no longer deems it useful for the current time. Deja Vu occurs when the signals to your short term memory either go to long term memory first or ends up in both at the same time. Seeing the sensory input in both the short term and long term memory confuses the brain into thinking that it has experienced the event in the past and at the current time creating the feeling that you have experienced before. 

Since it occurs when something goes wrong in the brain anyone who gets it on a daily basis should seriously see a neurologist on that.