The Japanese language is linguisitically quite distinct from various Chinese languages (Mandarin, Cantonese), but the Japanese adopted the Chinese writing system because the Chinese introduced writing to Japan. Chinese, as far as I know, does not alter words' endings, like English (for instance, climb, climbs, climbed, climbing). Japanese does alter these things, and more, so while Chinese characters were the first thing available, they're not exactly the best fit to the language.
The Japanese language then developed so that Chinese characters, called
kanji, are used for the roots of words, and additional characters called
kana are used for endings and other . . . strange syntactic functions. Now Japanese has two kana alphabets (more appropriately called syllabaries),
hiragana, which is used for native Japanese words, and
katakana, which is used to transcribe sounds and foreign words.
For instance, take the word 'to climb' in Japanese,
noboru. 'Nobo' is the root of the word, and is represented by a kanji character. Then, you add one or more hiragana characters at the end depending on what the word is being used for.
'He climbs.' NOBO-rimasu.
'He is climbing.' NOBOtte imasu.
'He climbed.' NOBOrima




a.
The kanji is the same in every one, but the hiragana changes. So if you're quickly scanning, you can recognize the kanji and know they're talking about climbing, even if you don't necessarily know at first glance in what form it's being used. The kanji is also the same as the Chinese character that means to climb (I think; this is usually the case for Chinese vs. Japanese, but there are always exceptions; don't quote me on it).
And as I type this, I really ought to be studying for my Japanese test tomorrow, which is a bit more complex, involving the proper etiquette for talking on the phone. Did you know that there's about four ways to say any verb in Japanese, depending on if you're being casual, polite, honorable, or humble?
For instance:
"Are you going to climb at Mt. Fuji this weekend?"
To my friend, Ikeda-san: "Shumatsu ni, Fuji-san de noboru?"
To a peer with whom I'm not close friends: "Shumatsu ni, Fuji-san de noborimasu ka?"
To a teacher: "Shumatsu ni, Fuji-san de onobo ni narimasu ka?"
Mrs. Horibe will climb at Mt. Fuji this weekend.
Talking about my teacher: "Horibe-sensei wa, shumatsu ni, Fuji-san de onobo ni narimasu."
I will cimb at Mt. Fuji this weekend.
Talking about myself (humble): "Watashi wa, shumatsu ni, Fuji-san de onobo shimasu."
Don't get me started on how the word 'one' in 'one person' and 'one pencil' are completely different. Hitori and ippon enpitsu.