Although this document is a tutorial and as such doesn't even tend to cover all PHOEBE aspects, a few introductory lines are in order. Let us start by explaining the name: PHOEBE stands for PHysics Of Eclipsing BinariEs.
Probably the most important thing for any new PHOEBE user is to understand the limitations and capabilities of this software. Although PHOEBE aims to be as useful as possible, it still tends to follow the basic principle of simplicity. In other words: although PHOEBE may assist you in solving your specific problem, it won't write an article for you or even make you a good cup of coffee; that is still up to you.
To describe PHOEBE in one sentence: for a set of user-supplied experimental light curves and radial velocity curves PHOEBE estimates physical parameters of an eclipsing binary that theoretically best matches the data.
The basic goal of PHOEBE is to aid you with intuitive interface through the pain of solving this problem. Since the dimension of the parameter phase-space is tremendous and the inverse problem for eclipsing binaries itself highly non-linear, this task is hard to live up to and PHOEBE is thus subject to constant changes and improvements. Hopefully each new version converges to a global optimum.