Blank stairs.

Sometimes I like taking the stairs rather than the elevator. Down, anyway. Up is a lot of work, you know. 

Most office buildings have lots of carpet around, or some kind of mild, decorative flooring. But stairs are not part of the official expected-use area. Unless they're part of a sweeping entrance or act as a funky floor connector, stairs are part of the secret bones of a building. They're tucked away behind barely marked doors, sometimes sealed off with the threat of automatic fire alarms. It's a shame because they're kind of cool. 

Stairs are usually seen in action movies, because if you're being chased you can't wait for the elevator. So you run down them, slide down them, fall down them; you get shot at from one flight to another, especially if it's a stairwell with a big empty space for the stairs to curve around so the bad guy can see you. The camera can watch you from above or below. Stairs are almost a distinct character in films like The Third Man.

The stairs can get all scary and bendy, like in Vertigo; you can fall down many, many stairs like Groucho Marx in A Night at the Opera.

Stairs are paradoxical. They are part of the structure, but they imply movement. Stairs lead, stairs run, stairs access; no one lives on stairs. People on stairs are always going someplace else.

Unless you're on the landing, panting like your lungs are trying to escape your chest. Stairs are great exercise.

So thank your friendly neighborhood stairs. Without them, architecture would never have gotten off the ground.