Japanese writing styles question?

Question:

Hello, I'd like to ask a few questions about the various writing styles in Japanese

1. How many are there and what are they?
2. Can all words be included in these writings?
3. Why are they more then one writing types?
4. What's the difference between ALL of them?
5. What are the certain writing styles used for? Is one more formal than the other?
Thank You

Answer:

There are four Japanese Writing styles Hiragana, Katakana, Kanji, and Ramaji.

Hiragana
The first writing system that is taught to young Japanese schoolchildren is hiragana. This system consists of about 46 symbols. Each symbol stands for a different phonetic sound, and all of the words are spelled phonetically. In Japan, they mainly use hiragana in school, manga (similar to comic books), newspapers, magazines, and video games. Hiragana is often put above kanji symbols in newspapers and magazines for those who cannot fluently read kanji. It’s also used to write words that there are no common kanji for.

Katakana
Katakana, like hiragana, consists of about 46 different symbols and is used to spell out words phonetically. However, it differs from hiragana in the fact that it is used only to spell out words foreign to the Japanese language. Examples of words that would be written in katakana would be foreign names or companies/businesses.

Kanji
This is the most difficult writing system that the Japanese have. There are 1,945 standardized symbols that one must memorize before being considered a fluent writer/reader of kanji.
Kanji is different from hiragana and katakana because every kanji symbol stands not for a sound, but for a specific object, word, or phrase. Some kanji are very simple to write, but other kanji are more complex. There are basic rules for writing kanji. For every kanji symbol, there is an assigned stroke number. The stroke number is important because it tells the writer how many times he/she should have to pick up their pencil while writing a symbol. Here are some basic kanji-writing rules:
1) Horizontal lines are always drawn before vertical.
2) Horizontal lines are drawn from left to right.
3) Vertical lines are drawn top to bottom.

Romaji
Romaji is the English, or Roman-derived alphabet, used to spell out Japanese words. There are different systems of Romaji.Romaji is often used in Japan on signs and notices for the sake of helping out foreigners/tourists.

EDITED

I study the Japanese language for the sake of one day becoming a fluent writer, reader, and speaker of Japanese/Nihongo (Japanese in Ramaji) / 日本語 (Japanese in Kanji)