Airline Codes verses city codes?

hi i was just wondering what the difference is between airline codes and city codes?

Airline codes - IATA airline designators, sometimes called IATA reservation codes, are two-character codes assigned by the International Air Transport Association (IATA) to the world's airlines in accordance with the provisions of IATA Resolution 762. They form the first two characters of the flight number.
Designators are used to identify an airline for all commercial purposes, including reservations, timetables, tickets, tariffs, air waybills and in airline interline telecommunications.

City codes - An IATA airport code, also known an IATA location identifier, IATA station code or simply a location identifier [1], is a three-letter code designating many airports around the world, defined by the International Air Transport Association (IATA). The characters prominently displayed on baggage tags attached at airport check-in desks are an example of a way these codes are used.
Example of IATA airport code printed on a baggage tagThe assignment of these codes is governed by IATA Resolution 767, and it is administered by IATA headquarters in Montreal. The codes are published biannually in the IATA Airline Coding Directory[1]. The codes are not unique: 323 of the possible 17,576 codes are used by more than one airport.
While the IATA codes are the most familiar airport codes to passengers, the 4-letter ICAO airport codes are becoming increasingly common within aviation. All international flights are flight-planned and tracked using ICAO (International Civil Aviation Organization) designators, and most GPS databases use ICAO codes to avoid conflicts with three-letter navigation-aid codes. Many countries, such as Canada, no longer use IATA codes in their official aeronautical publications.

I guess the airline codes refer to the carrier, like United, American or British Airways. The city codes refer to the airports, like Pittsburgh, John F Kennedy/NYC, or London/Heathrow.

u probably mean airport codes. Airport codes is the abbreviation of airport names e.g jomo kenyatta international airport will be JKIA city codes is the abbreviation of city names e.g nairobi will be NRB

Theres a big difference. Airline codes is usually the abrivitated code they use for an airline, for example British airways is BA. Kenya airways is KQ, etc etc. City codes are usually abriviations of cities, such is Nairobi is NBI or Lusaka is LSK London is LON, ofcourse airports are determined by other codes (eg Nairobi NBO and London Heathrow LHR, Lusaka by LUN). If u need more info get back to me.