Hong Kong has retained control of its own immigration and as a result foreign nationals of most countries can visit Hong Kong visa-free. However, this means that you will need a separate visa if you decide to enter Mainland China or Macau during your visit.
The only way to enter Hong Kong internationally is via plane through the Hong Kong International Airport, which is also called Chek Lap Kok, named after the island it was built over.
Hong Kong International Airport (HKIA) is an extremely functional and modern airport, which was designed by world renowned architect Norman Foster. The passenger terminal is the world's largest single airport terminal covering 1.27km. It is also the world's fifth busiest international passenger airport and sees an average of 750 aircrafts taking off and landing every day.