Air Flights

London has 6 key airports but none is called London Airport.
The largest, Heathrow, has four terminals, a railway link to Paddington Station and two tube stations on the Piccadilly Line. It's a very busy airport with huge variety of flights and airlines.
The second city's airport is Gatwick. It has two terminals and even its own railway station where you can get from Victoria Station.
The third, Standsted, is used by many cheaper airlines and can be reached from Liverpool station. It's used by many cheaper airlines.
City Airport is mainly used for short flights to Europe or within UK.