The typical order to master the Japanese writing system is a follows:
The Japanese writing system uses two syllabic scripts, known separately as hiragana （ひらがな）and katakana (カタカナ) and collectively as kana, and thousands of Chinese characters known as kanji (漢字). Each script serves a different function. Hiragana are used for grammatical elements and for words that do not use kanji (or for words where the author doesn’t know the kanji). Katakana is mostly used to write borrowed words of foreign origin, and onomatopoeic sound effects. Kanji is used for words of both Japanese and Chinese origin, as well as many Japanese names.
The earliest written form of Japanese was based on kanji. In this system, known as man’yogana, these kanji were used for their pronunciation rather than their meaning. Because this system was quite complicated, kana were invented as a way to simplify it. As a result, each hiragana and katakana character comes from a simplified version of a man’yogana kanji. If you look at some of these man’yogana kanji and their simplified kana equivalents side-by-side it is easy to see how they came to be.
There are 46 characters in the hiragana and katakana scripts, for a total of 92 characters in all. These characters represent sounds, specifically syllables. A syllable is generally made up of a consonant plus a vowel, though there are some that are only a vowel. In Japanese, there are five vowels: a, i, u, e, and o; and fourteen basic consonants: k, s, t, n, h, m, y, r, w, g, z, d, b, and p.
The Hiragana (ひらがな) syllabary is used for words that do not use kanji, grammatical elements such as particles and inflected verb and adjective endings (known as okurigana, 送り仮名), and for writing the readings of kanji characters (known as furigana, ふりがな). Furigana are small hiragana symbols placed above or to the side of a kanji character that indicate how it is read. While furigana are mostly used to aid children and foreigners learning Japanese, it is also used when the reading for a kanji is particularly difficult or uncommon. Hiragana symbols are characterized by their curvy, flowing lines.
The Katakana (カタカナ) syllabary is used for words of foreign origin (known as gairaigo, 外来語), onomatopoeic words that indicate sounds, scientific names, and also for emphasis, much like how italics are used in English. Katakana symbols are characterized by their angular, boxy lines.
Kanji (漢字) are Chinese characters that have been adapted into Japanese over many years. The characters were originally pictures of people, animals or other things, but over the centuries they have become increasingly stylized and most no longer resemble the things they represent. Kanji are made up of smaller parts known as radicals. Many characters have been combined with others to create new ones. When written on the page, each character is given exactly the same amount of space, no matter how complex it is. In written Japanese, there are no spaces between characters.
The number of kanji in existence number into the tens of thousands, but the good news is that a large number of these are rarely used variants, accumulated throughout history. The Japanese government has created a list of recommended characters known as Jouyou Kanji (常用漢字), which currently contains 1,945 characters (as of 2009). As this list occasionally undergoes revisions, it is possible that this number may increase in the future. Studies have shown that full literacy in the Japanese language requires a knowledge of around two thousand characters.
Most kanji have at least two different kinds of readings: kunyomi (訓読み), which is the Japanese reading, and onyomi (音読み), which is the original Chinese reading. The kunyomi is usually used when the kanji stands alone, and the onyomi when it is part of a compound. To give an example, the kanji 水 (“water”) can be read as either “mizu” (kunyomi) or “sui” (onyomi). However, there are exceptions to this rule that simply must be remembered.
Romaji (ローマ字) is Japanese transliterated into the Roman alphabet. With Romaji, one can read Japanese without any prior knowledge of the Japanese writing system. There are several systems of Romaji, with the Hepburn system being the most widely used.