What is the difference between sun and moon letters in Modern Standard Arabic and what are they?

Answer 1

Sun and moon letters in Arabic are a group of letters that come after the definite article ال and make you either pronounce or omit the pronunciation of the ل of the definite article.

1. If you encounter a sun letter after the diffident article, just omit pronouncing ل of the definite article. For example the word: الشّمس will be pronounced as ash-shams and not Alshams.
2. If you encounter a moon letter after the diffident article, just pronounce ل of the definite article. For example the word: القمر will be pronounced as alqamar.

Here are the moon letters:

ا، ب، ث، ج، ح، خ،ع، غ، ف، ق، ك، م، هـ، و، ي

The rest are the sun letters.

I hope this helps!

Answer 2

Just to clarify:

The moon letters are 14:

أ، ب، ج، ح، خ، ع، غ، ف، ق، ك، م، ه، و، ي

The letter ث is NOT between the moon letters. It is a sun letter.

The sun letters are 14 too (total letters in the Arabic Alphabet are 28):

ت، ث،، د، ذ، ر، ز، س، ش، ص، ض، ط، ظ، ل، ن

Ahlan wa Sahlan!