Story in Parts is an event in which prompts are given to groups of people, each of whom writes a different part of the same story, without the knowledge of what the other groups are writing.
After all the groups have finished collaborating and writing, each part is read in succession to see how much continuity and ridiculousness we managed to achieve (here's a clue, usually one is pretty high and the other pretty low).
If you're not into writing, no worries! You can contribute to discussions, throw out the occasional idea, or just hang out and watch the fun. See you there!