typedef

  typedef existing-type new-type;

The typedef keyword allows you to create a new alias for an existing data type.

This is often useful if you find yourself using a unwieldy data type -- you can use typedef to create a shorter, easier-to-use name for that data type. For example:

  typedef unsigned int* pui_t;

  // data1 and data2 have the same type
  piu_t data1;
  unsigned int* data2;