The three writing systems used by Japanese people are called kanji, hiragana, and katakana. Originally there was no Japanese system of writing; kanji was first adopted from Chinese characters, but only certain people, priests for example, were well-enough educated to learn this complicated form of writing. Kanji was simplified into hiragana, first known as the "women's alphabet" because it was simpler and easier to learn. Hiragana was further simplified into katakana.

Kanji

The characters for the Japanese alphabet known as kanji are taken almost directly from the Chinese alphabet, though some are altered slightly. The characters themselves mean "Chinese" (kan) and "character" (ji). In order to read a Japanese newspaper, book, or similar material, one must learn all of the approximately 2,000 Jooyoo (Education) Kanji. Most Japanese people achieve this level around the age of 11. Kanji are used more to convey meaning of words than grammarto convey the meaning of words; rather than invariably representing a syllable, as both hiragana and katakana characters do, each character can represent single or multiple syllables, but always has the same or similar meaning in different contexts. For example, the character below:

This character can be read "hi," "bi," "ni," "nichi," or other ways, but it always means "day," "sun," or "Japan," all of which are related meanings.
The meanings of names and longer words can be determined easily, by determining the meaning of each character.
An example of a place:

Wakayama (wa-ka-yama) = "peace" "song" "mountain"
An example of a name:

Takemura Aya (take-mura aya) = "bamboo" "village" "colorful one"

Hiragana

Hiragana characters are simplified versions of kanji characters. Each represents one syllable, but has no separate meaning by itself. Below is a syllable chart:

This method of romanizing Japanese words is probably the most popular among the Internet community, though there are several others; for example, one substitutes "si" for "shi" and "ti" for "chi," etc. Below are these syllables in hiragana:

These syllables can be changed to form the missing ones; these are not the only sounds of the Japanese alphabet. The dots and circle change the sounds of certain characters. Adding the dots to the "k" column will make the "g" sound, to the "s" column will make the "z" sound, and to the "t" column will make the "d" sound. With these you can form "ga," "gi," "gu," "ge," "go," "za", "ji," "zu," "ze," "zo," "da," "ji," "zu," "de," and "do." Adding dots to the "h" column produces the "b" sound, and adding the circle produces a "p" sound, forming "ba," "bi," "bu," "be," "bo," "pa," "pi," "pu," "pe," and "po." Additionally, adding a smaller "ya," "yu," or "yo" will change the sound of any syllable ending in "i" to one ending in "ya," "yu," or "yo." A few examples are below, to clear up any confusion.
= "gi" = "bi" = "pi" = "nya" = "byu"
Any word that is written in kanji can also be written in hiragana. In fact, many words (especially verbs and adjectives) are always a mix of the two alphabets. Words written in hiragana are always native to the Japanese language.

Katakana

Katakana is in many aspects similar to hiragana. The same syllables are used, and katakana characters are even further simplified hiragana characters. The main difference is that katakana is used for words that are foreign to the Japanese language. See the hiragana chart above for the romanized syllable chart. Below are these sounds in katakana: