I wanna say last I read, the "0 and 1 at the same time" is a vector value of 0 and 1. For example, if you had a vector with 2/3 parts 0 and 1/2 parts 1, it would represent a specific state. Each portion of the 0 or 1 is a real number, so it could essentially represent an infinite number of states. Similar to an (x,y) coordinate system. You have your origin at (0, 0) and a point at (0.3, 0.5) that vector would determine the state of the qubit. This of course is simplified down.