Welcome to the Kanji section of our suite. Kanji are basically characters that represent a whole word, not just a sound. As you might guess, there are a large number of these, some rather complex. There are around 2,000 common use Kanji and over 6,000 Kanji in all. Kanji were originally Chinese characters that were borrowed centuries ago and which have become more distinctly Japanese over time.
Hiragana and katakana both descended from kanji as basically simplified characters based on the kanji. These characters represented sounds rather than entire words. You might want to focus on learning hiragana and katakana before really getting into the kanji, as this is also the order in which they are learned in Japan. Also, the furigana for kanji (and even for katakana for small children) is written in hiragana. Furigana are basically tiny hiragana characters written above kanji in horizontal text and to the right in vertical text to help readers who aren't yet familiar with kanji. These are often seen in children's books, anime, manga and on signs or in newspapers etc where readers might be unfamiliar with many kanji.
For a more thorough explanation of kanji, please see the Wikipedia article on Kanji. It's very informative and well worth your time to give you a better understanding of what you're getting into if you're new to this.
We'll be expanding this section as we write descriptions for all the individual programs that make up the Kanji section of the Japanese Learning Suite. Please check back later for more information.