Japholic said:
umm.. well i understand a bit. But i dont get when to use these?
in Japanese you have a phonetic writing system right? so when do i know if i am to write the word "otokonoko" with these phonetics or Kanji? and how many kanji are there really? one for each noun or something`?
i might be able to attent a very basic conversation in japanese but when it comes to writing it.. :?
Ah, now I get what you're after. To answer honestly, it's completely up to you when to use kanji and when to use hiragana/katakana, but that's something that you'll figure out as you develop your language skills. To offer up my personal opinion, I tend to write in a way that my sentences are easily readable. As the Wikipedia article earlier mentioned, logographic languages are often notable for the speed at which they can be read--since Japanese does not use spaces, kanji serve as a practical method for visually breaking up sentences. Take the following three examples:
わたしはちょっとともだちのところへあそびにいってくるよ。
私はちょっと友だちの所へ遊びに行ってくるよ。
私は一寸友達の所へ遊びに行って来るよ。
All three of these sentences are read the same way, and all three are correct. To a beginner who is likely reading character-by-character, the first sentence is most likely the easiest to read. Most Japanese speakers, however, will find the second sentence easiest to read as it has a good mix of kana and kanji that are effective in breaking up the sentence into easily digestible chunks, which is good when you are reading words and phrases at a glance. Incidentally, that is not the only way to do it; it's just the way I chose (友達のところへ is also a good choice imho).
The third sentence, however, is a little too cluttered to read, having used kanji virtually wherever possible. It's certainly readable, but it might cause someone to pause along the way.
As for your question as to how many kanji there are, the answer is a lot. Almost any proper word has a kanji character (or several) associated with it, but which ones are actually
used is another question. Government documents are limited by law to use the 1,945
Jouyou Kanji for words and the 983
Jinmei-you Kanji for names, and many newspapers generally follow the same guidelines. However, the Jouyou Kanji are a bit outdated, providing such anachronisms as ほか being an unacceptable pronunciation for 他 (the correct Jouyou character is 外) while words such as 朕(ちん, a term once used only by the Emperor to refer to himself) remain on the list, so this should not be seen as the be-all end-all of kanji lists.
For right now, then, you need to focus on what is readable to
you and learn the basic vocabulary rather than worry about kanji just yet. If you can pick one or two up now, though, then go for it, because I can guarantee that the words you're learning will use those characters.