We use honorifics "-kun" to refer to boys or men that we're close with and "-chan" for girls or women we are close with.
Honorifics are words used to show respect to someone or show closeness to a person. For most Asian countries, honorifics are used closely with a person's name.
Friend: What does "-kun" and "-chan", mean?
You: It's an honorific for boys and girls we are friends or are close with. "-Kun" is used for boys while "-chan" is used for girls.
Example: Good morning, Kei-kun./ Good morning, Yuri-san.
Honorificsとは、ある人に敬意を表したり、人との親しさを表して使われる言葉です。ほとんどのアジア諸国では、honorificsは人の名前と一緒に使われます。
【例文】
友人: What does "-kun" and "-chan", mean?（くんやちゃんはどういう意味？）
あなた: It's an honorific for boys and girls we are friends or are close with. "-Kun" is used for boys while "-chan" is used for girls.（友達や親しい男の子や女の子につける敬称だよ。くんは男の子に、ちゃんは女の子につけるよ）
Good morning, Kei-kun.（おはよう、けいくん）/ Good morning, Yuri-san.（おはよう、ゆりちゃん）
An a sign of respect we say Kun after a boys name and Chun after a girls name.
"An a sign of respect we say Kun after a boys name and Chun after a girls name." This explains to the person that by saying Kun after a boys name and Chun after a girls name you are showing respect.
We use San after the name of an adult.
"An a sign of respect we say Kun after a boys name and Chun after a girls name."
（敬意を表す意味で、男の子の名前の後に”KUN”、女の子の名前の後に”CHAN”をつけます。）
このように説明することで、男の子の名前の後に”KUN”、女の子の名前の後に”CHAN”をつける呼び方はより丁寧なものであると伝えられます。
大人の場合は名前の後に”SAN"をつけて呼びます。
As other posters have explained, these type of words or syllables are called "honorifics", like "Mr." in English.
If you call it a "suffix", then it is clear to the person that you are talking to that the syllable comes AFTER the word to which it refers, not before.
The opposite of "suffix" is "prefix", that is, one syllable or more that you put BEFORE a word, not after.
Some languages (like Turkish) have syllables you put in the middle of a word. This is called an "infix". But English DOESN'T really have these -- thank God! English is already too difficult!
Kun is used after a boy's name an chan after a girl's name as a sign of respect.
*Kun is used after a boy's name an chan after a girl's name as a sign of respect.- This means that you use kun and chan as a way to respect other people.
A:Kun is used after a boy's name an chan after a girl's name as a sign of respect.
B:Oh that is nice
A: For example John Kun or Sofia Chan
Kun is used after a boy's name an chan after a girl's name as a sign of respect.
「Kun は男の子の名前の後に使われて、Chanは女の子の名前の後に、敬称として使われます。」
Kun やChanをつけると丁寧な呼び方になるという意味です。
A:Kun is used after a boy's name an chan after a girl's name as a sign of respect.
（Kun は男の子の名前の後に使われて、Chanは女の子の名前の後に、敬称として使われます。）
B:Oh that is nice
（それは良いですね。）
A: For example John Kun or Sofia Chan
（例えばジョン君とかソフィアちゃんというようにも使えますよ。）
In Japanese, the equivalent of 'master' is 'kun'; and 'miss,' 'chan.'
Explanation: MASTER is the title given to a boy, and MISS is the title given to s girl in the UK, though neither are common in casual speech.
Example sentence:
"Miss Wood is waiting for you at reception."
イギリスでは、MASTERは男の子に、 MISSは女の子につけられる呼び方です。どちらもカジュアルな会話で使うことはありません。
例文：
"Miss Wood is waiting for you at reception."
ウッドちゃんは受付であなたを待っています。
イギリス 
フィリピン 
南アフリカ 
アメリカ合衆国 
