The postcard today is primarily an atavistic vacation novelty, but prior generations used these paper rectangles to convey a whole host of emotions.
That said, it's not always clear what emotions the following postcards were meant to impart, but good gravy, are they sinister, weird, or weirdly sinister. I'm pretty sure all of them were available for purchase at the Twin Peaks post office. Let's start with the top image, which was sent to negligent children who missed Sunday school.
This mid-1900s postcard is either an advertisement for Mooseheart, Illinois or an invitation to worship a death god who dresses like an Oldsmobile dealer.