 <p>As it's already mentioned by taocp, the line refers to member initialization list.</p> <p>There are couple of ways to initialize members 1. member initialization list (efficient approach) 2. using assignment e.g. players = 10</p> <p>It might not make any difference for built-in types e.g. int, char but if you are assigning big objects then use member initialization list. Constructor/ Destructor gets called in assignment which is definitely not warranted</p>