The <=> operator in C++ is called the spaceship operator or the three-way comparison operator.

It was introduced in C++20 and is used to compare two values and return a result that indicates if the left value is less than, equal to, or greater than the right value.

Some key points about the spaceship operator:

• It returns 0 if the values are equal.

• It returns -1 if the left value is less than the right value.

• It returns 1 if the left value is greater than the right value.

• It allows a single operator to handle all comparison cases.

• Often used to simplify implementation of the compare function for types.

• Replaces the need for multiple operators like <, >, == etc.

Usage example:

int x = 5, y = 10;

auto result = x <=> y; // result == -1

The spaceship operator is especially useful with C++ templates and generics, as it provides a consistent way to define ordering for any custom types.

So in summary, the <=> operator provides a compact way to handle all comparison scenarios in a single operator, simplifying code and generic programming.