Question About Alpha/Omegas (And Betas)

Hi, luvs! Question for you, O Mighty Flist: I've been reading some Alpha/Omega fics and checked it out on Fanlore to find out exactly what it was all about, but my question is: when you write an Alpha/Omega fic, are there hard-and-fast rules you must follow, or can you take the general concept and create your own world around it? There are similarities to D/s in this and I'd like to try my hand at it. Thanks! :)