Katakana or Hiragana ?

Few pas days i learning japan and i have some questions,
Is true "Hiragana" Based for childrens (books etc)
Katakana ? Using for and where ?
And what in Japan language using people Katakana or Hiragana ? ^_^

I very like Japanese !

I cannot fully get what you mean but let me guess.

While Hiragana and Katakana are just signs for sounds,
Kanji are letters with both meaning and sounds.

For human language is basically meant to be spoken,
every words have sounds, and can be written with Hiragana and Katakana.

But usually in Japanese, many verbs and almost all nouns have spellings
of Kanji or Kanji combined with Hiragana.

For example, the word "flower" can be translated to
Japanese word which reads/sounds "hana",
and this is written "はな" in Hiragana,
and spelled "花" in Kanji.

In like wise, the word "run" is pronounced "hashiru",
written "はしる" in Hiragana, and spelled "走る" using Kanji with Hiragana.

So when one learns Hiragana,
he can write Japanese by matching the sound with Hiragana.
But to write in more former manner,
one has to know its corresponding Kanji or Kanji-Hiragana spellings.

In other words, while writing whole sentence with Hiragana looks very childish,
it doesn't mean adult write whole sentence with Kanji.
Some words has spelling which only uses Kanji, but other words has spelling which use both Kanji and Hiragana.

As for Katakana, it is usually used to spell words of foreign origin,
which do not have Kanji spellings.
For example, the word "computer" is translated "konpyu-ta-",
and spelled "コンピューター" using Katakana.