Airline Alliances have respective member loyalty programmes that all tie together under one umbrella.
You can use your perks such as lounge access, business class check-in and miles from one airline on to another member airline of the alliance.
Airlines also have code-share agreements where you can earn miles, burn miles, fly and connect on a different airline outside of the alliance such as Etihad and Emirates ( who belong to no alliances ).
There are 3 Airline Alliances.
Tip: Use the links to find out about lounges at terminals where you will pass through or transit at.
1) Star Alliance. – SAA is here.
Access STAR ALLIANCE HERE.
2) Oneworld Alliance.
Access ONEWORLD HERE.
3) Skyteam Alliance.
Access SKYTEAM HERE.