It's one of the japanese alphabet ^^ You have the kanjis, that represent words, then the hiraganas and the katakanas, where symbols represents syllable and you make words with them, and then the romaji alphabet that is the same as our. Yes, all of that seems to be very complicated ... And it is !
I tried to learn it this way once ^^ I seriously advise you to learn at least the most important kanjis, because in every websites or everywhere in japan you won't find many things with the abc alphabet...
Yes of course :) How do you want to learn the words otherwise if you don't know their writting at all? But in Japan I guess they don't use our typing at all. So, in any case, unless you only plan to speak it orally, you'd better learn their alphabet.