Just as curiosity Fanites, Serbo-Croatian is one of the rare languages who´s letters allways respect the rule one letter, one sound, and allways that sound. As from the explanation Timbou provided next, you can easily see that p is p and f is f, and if you read it pronouncing the sounds the letter should supose to have, regardless of the other next to them, as in English, you´ll most certainly easily read it. Basically, the only letters you may find difficulties to know how they sound are the ones with accent (ć (tsh), č (tch), đ (dy), š (sh) and ž (zh), all the others are simple and basic. I hope you understood this improvised explanation of mine. )