Type letters into the box and anyone viewing the project will be able to see all the characters that you write in the order that you wrote them using a simple number-letter encoding system. While not intended to be a "chat" system, it can be used as such for any multiplayer project.
The system on handles letters and spaces, so numbers, commas, periods, etc. will glitch and appear as the last-typed letter. This can be modified for any number of characters, however.