Question

I want to clarify whether different instances of an Objective-C class share static variables that occur inside methods, or if each instance gets its own copy:

- (void) myMethod {
    static int myVar = 0;
}

Answer 1

It’s the same as a static variable in C; the instances will share the variable. If you want each instance to have its own copy, you want an instance variable (declared in the @interface block).