Is there a concept of after life in Buddhism?
There are 2 types of Nibbana which are:


sopadhishesa-nirvana (nibbana with a remainder) - while alive 
parinirvana or anupadhishesa-nirvana (nibbana without remainder, or final nirvana) - after death 


Nibbana is being blown out. So once you die for a person who has attained Nibbana does not go any where. The person is extinguished. This is like when you blow out the candle the flame does not go any where. The conditions for combustion are not there hence it extinguishers. This is similar to Nirvana. Conditions for future rebirths are no longer present hence you get extinguished.