What is a wave function?

The idea that an elementary particle has a probability distribution of its possible locations at any point in time was devised by the one and only Erwin Schrödinger in 1926. Obviously, we as humans can perceive the things around us with a level of certainty. There is a computer in front of me, for example. I am sitting on a chair. There isn’t much question to be had about those things, and I don’t need to observe my dining table downstairs to know that it's still there. At the quantum level, however, things become more unpredictable. 

Suddenly, we don’t really know where everything is, we just know where things might be. We can create a probability distribution of the possible locations of a particle and use that to predict its location when we’re not observing it. When we do observe it though, this probability distribution (the wave function) collapses. This means that we have measured a position with certainty, so there is no chance of the particle being elsewhere at that point in time.

~Srimaye Peddinti