Confusing icons

1. Why is the play icon a triangle?
2. What is the share icon called?
3. What is the play symbol?
4. Who invented the play icon?

Why is the play icon a triangle?

Where Play Came From. The short answer is no one really knows. Gizmodo says that it's from the 1960s when audiovisual was still reel-to-reel. The idea back then was that the triangle actually was an arrow, indicating which way the reel went, but this is pretty much just speculation.

What is the share icon called?

The Open Share Icon (or Shareaholic icon) is designed to help users easily identify shareable content.

What is the play symbol?

The “Play” arrow — a triangle pointing to the right — is possibly the most ubiquitous modern technology symbol there is.

Who invented the play icon?

Reportedly introduced in the 1960s by Swedish engineer Philip Olsson the play arrow was first designed to indicate the direction where the tape would go when reading on reel-to-reel tape players. Since then, we switched from cassettes to CDs, from the iPod to Spotify, but the media controls icons remain the same.