As already described earlier, you need not learn the characters of Japanese eagerly.
I write the explanation about the characters of Hiragana, Katakana and Kanji, in that order.
But please read as your new knowledge.
Each syllable I explained in the page of Lesson-1 has a unique Hiragana character.
Ancient Japanese people used Kanji characters imported from China to write Japanese sentence.
For each Japanese syllable, a Kanji character with similar Chinese sound were selected.
Because it takes a lot of trouble to write Kanji character, the characters gradually became cursive style to speed up the writing.
As the centuries roll by, the characters were simplified, then they became Hiragana.
The languages using alphabet have capital letters and lower-case letters.
But Hiragana has such different letter set.
Instead it has small characters with special function.
The syllable of “consonant + Y + vowel” is written as “character of ‘I’ column + small character of ‘Y’ row”.
And small “tsu” character is used as the sign of pause sound.
Each character in Dakuon group is made by adding two dots like double acute to the corresponding character with unvoiced consonant.
Only “H” row is unusual.
Phonetically, there is not voiced “H” consonant.
But “B” consonant corresponds to the voiced “H” in Japanese.
And original unvoiced consonant “P” is made by adding a sign of small circle to the character with “H” consonant.
The relation between Seion and Dakuon often appears at the time of inflection or combination of words.
But the rule is not so regular.
Therefore, you should worry about that.
About long vowel, the notations are generally as follows.
aa : (A column character) + (A character)
ii : (I column character) + (I character)
uu : (U column character) + (U character)
ee : (E column character) + (I character)
oo : (O column character) + (U character)
“ee” and “oo” are irregular.
Please check the case of “Tokyo” (The pronunciation is “Tookyoo”) in above table.
Situation that Hiragana is used
Hiragana is the basic character set for Japanese.
Even if you write Japanese sentences only in Hiragana, you can convey your messages completely.
In common Japanese sentences, many of nouns and stem of verb and adjective are replaced to Kanji character as possible and the rest is written in Hiragana.
Of course, it doesn’t mean that Kanji is more important than Hiragana.
Hiragana is the base of Japanese grammar and Kanji is the character that we can catch the meaning of the word visually in a moment.
There is no Japanese sentence without Hiragana.
When you travel around Japan, you see many word in only Kanji word. They are almost nouns.
Because Hiragana is most important character set, it is taught in the first grade in elementary school.
After that, the pupils learn a lot of Kanji characters in sequence during elementary school and junior high school.
They write a composition in only Hiragana at first, then they come to be able to write a composition with many Kanji characters when they graduate the junior high school.
Please know that Hiragana is the character set which is the base of Japanese.
As an additional explanation, I write about Japanese punctuation.
In Japanese, it has some punctuation marks.
The function is the same as English ones.
But the form is a little different.
Please check the following figure.
Japanese comma is a short line to the lower right.
And Japanese period is a small circle.
Quotation mark is a right-angled line.
Question mark and exclamation mark are the marks from English, but they are used in the same way.