I take it you are kind of new to fish keeping?
Carbon is chemical filtration... it is used to remove chemicals from the water. Ammonia Chips are another form of chemical filtration used to take ammonia and other nitrogen compounds out of the water.
After a fish tanks has been established for a while a colony of bacteria builds up that consumes ammonia and converts it into nitrites.
Then a different strain of bacteria builds up that processes the nitrites to nitrates. The process of building up these strains of beneficial bacteria is called tank cycling.
Once your tank is cycled and the bacteria is doing its job chemical filtration is for the most part not needed. If you do some googling on Aquarium cycling there are several articles that will explain the concept better than I can.