Foundation 2: Sifat al Ardiyyah (Order that letter comes)
After knowing Sifat al Asliyah (Intrinsic Characteristics), we have to study extrinsic characteristics of the letters which is called Sifat al Ardiyah. Here pronounciation of letter is mainly based on the order the letter comes. They can be mainly catergorized into 8:
1. Rules of Tafkheem and Tarqeeq: 
2. Noon Sakinah and Tanween:
3. Meem Sakinah: 
4. Laam Sakinah: 
5. Ghunnah: 
6. Idghaam: 
7. Rules of two consecutive letters: 
8. Rules of Madd: 
Reference:
Notes taken from KIU Tajweed classes of Shaykh Ahmad Wahab (Hafidhahullah)