You can forget how quickly things change around you. Taking photographs helps. I have literally thousands – most however have gone into to that it was the 70s, 80s or 90s era etc. And was that photo taken on the first trip to the Zoo or the 15th?
However digital cameras have changed that in as much as it is easier to record when a photograph is taken.
I took this photo of the rainbow over the river, with the Sun reflecting off the windows of the building.
Then awhile later I took these, slightly different angles, where you can see that the building is now wrapped, ready for demolition.