im 21 in a few months and ill have 3 years ncb, so i think its time for a propper car, im thinking about a mk2 1.8 8v and just trying to learn as much as i can on here before i take the plunge, need to know what im letting myself in for

just a couple of quick questions, can any kind person tell me what a PB head is and what is ABF?
thanks
DW