At the end of each ayaat there is a circle with the ayah number in and a letter above it.what do these letters mean?..

Salaam alaikum
I can recite the Qur’an, but i am not sure about some of the tajweed rules: At the end of each ayaat there is a circle with the ayah number in and a letter above it.what do these letters mean?
For example I heard miim means you have to stop, and lam-alif means carry on.  Please help. Jazaakallah khair.
ma assalaam

Answer

Wa alaikum assalaam wa rahmatullahi wa barakatuh.

The markings at the end of aayaat have been dropped from the Medinah Printing Complex copy of the Qur’an because stopping at the end of each aayah is sunnah.  It is not compulsory to stop at the end of each aayah, but since it is preferred, it is much better to stop at the end of every aayah no matter what symbol is written. Therefore the  symbol at the end of an aayah should not be thought of as a preference or a command.   The  symbol does mean you should stop because of the meaning.  This in only applied when joining aayaat together. 

Wa iyyaakum.

Wa assalaam alaikum wa rahmatullah