A childhood belief about ghosts

when i was little the window to my room faced a portion of the street. at night i would see a light travel across my wall from one end to the other. it was always square shaped and happened sparadically (spelling). i assumed the lights were ghosts in my room. it wasnt until years later i realized everytime i saw those "ghosts" i heard a car drive by. it was the headlights shining through my window as they drove by. whenever i see a light go through the window at night, the first thing i think of are ghosts.