Moon and Sun Letters
- In Arabic the ال prefix comes before nouns to make them definite.
- The ل in this prefix, sometimes forms a shadda with the letter after it and sometimes is recited openly with a jazm.
- If any of these letters ء هـ ب غ ح ج ك و خ ف ع ق ي م come after ل then it is recited openly with a jazm. These letters are called qamari, or moon, letters. The name comes from the word for moon اَلْقَمَرُ.
- If any other letter besides the ones listed above comes after lam, lam forms a shadda with the letter after it. These letter are called shamsi, or sun, letters. The name comes from the word for sun اَلشَّمْسُ for which this rule applies.