Japanese uses three separate writing systems: hiragana, katakana, and kanji. Hiragana and katakana are phonetic systems and show the pronunciation of Japanese words. Kanji is the Japanese variation of Chinese characters and shows the meaning of Japanese words. The three systems are used interchangeably, and all three systems can often be found in the same sentence. The three systems are each reserved for different purposes.
In English, the order of the words is very important. For example, the sentences "Is it?" and "It is." mean different things. In Japanese, differences are often made by adding or changing the ending of words (using the previous example, one would say them as そうですか sou desu ka and そうです sou desu, respectively). A Japanese word has a stem called a "body", and additional parts (called suffixes). Changing the suffix can change the meaning or the grammar of the word.
After World War II, many English words entered the Japanese language (wasei-eigo). An example of one would be "アイスクリーム (romanized: aisukurīmu)”, meaning “ice cream”.
Sounds
Japanese has five vowel sounds that can have two different lengths. They are a, i, u, e, o. In IPA they are transliterated as /a/, /i/, /ɯ/, /e/, /o/; and they are pronounced in English[clarification needed] as ah, ee, oo (lips are unrounded),
Grammar
When foreigners speak Japanese, it is important they know how formal they must be when they speak to people you may or may not know. In Japan, it could be considered quite impolite (rude) if you are not formal enough.
In Japanese, sentences use subject-object-verb (SOV) word order, so the verb is at the end of the sentence and the subject is at the beginning. Many sentences have no subject, and the listener can infer the subject based context and the form of a verb.
In Japanese, Japan is called Nihon (日本), and the language is called Nihongo (日本語) (-go means language). Sometimes, the words Nippon and Nippongo are also used, but both words are now thought of as more nationalist, and Nihon is a more neutral word. The kanji of the word mean "sun-origin." Since Japan is at the eastern edge of Asia, to observers in China, the sun rose from the direction of Japan. That is why Japan is called "The Land of Rising Sun."
Japanese is also agglutinative language, especially in its verbs. Its words has a short "body," and prefixes or suffixes are easily added to change or to redefine the meaning.
Japanese words come from three main sources. The first is wago (和語), which are native Japanese words and can also be called yamato kotoba (大和言葉). The second is kango (漢語), which are Chinese loanwords. The third is gairaigo (外来語), which are loanwords borrowed from languages other than Chinese (usually English since the Second World War).
Hiragana is a Syllabary, meaning each character represents a syllable or vowel. Each character is a comprised of either a vowel, a consonant-vowel blend, or the syllabic consonant, n (ん). Hiragana is the standard, phonetic writing system in Japanese and is used for grammatical words or particles e.g. は、を (wa - Subject particle, o - Object Particle); words that don't have Kanji characters e.g. こんにちは (kon'nichiwa - hello); or for beginners to write Kanji. The symbols were originally adopted from Kanji characters and have changed overtime into their distinct, rounded shapes (e.g. 以 →い).[2]
Katakana is also a Syllabary, with each Hiragana character having a character in Katakana (e.g. あ = ア こ = コ). Katakana is used for impact (similar to italics in English) as well as gairaigo words and direct transliterations from English e.g. メニュー (Menyuu - Menu). Katakana was originally made by Buddhist Monks to teach Japanese people how to read Chinese.
Kanji is an adaptation of the Chinese logographic writing system, meaning each symbol was originally meant to look like the word it was describing. Each symbol can represent a word e.g. 音 (oto - sound) or a syllable in a larger word. There are multiple pronunciations for each Kanji character, categorised into On'yomi (音読み) or Kun'yomi (訓読み), depending on the word's origin.
References
↑"Världens 100 största språk 2010" (The World's 100 Largest Languages in 2010), in Nationalencyklopedin