C++ - colon after constructor

Question

What does it mean and do when you have a colon after the constructor?

MyClass() : something {

}

Answer 1

That signifies an initialization list.

Which can be used in inheritance (call base class) or for initializing member vars before the constructor/body is executed.

Here’s a simple ref: https://www.learncpp.com/cpp-tutorial/constructor-member-initializer-lists/