#import // Simple class @interface MyClass : Object { // instance variables int myVariable } // Class methods + myClassMethod; + (int)myClassMethod2; + (int)myClassMethod3:(NSString *)parameter; // Instance methods - (int)myInstanceMethod:(NSString *)text; - (NSString *)myInstanceMethod2:(int)parameter withText:(NSString *)text; @end @implementation MyClass + (int)classMethod { return [self myVariable]; } - (NSString *)instanceMethod { NSString *string = [[NSString alloc]initWithUTF8String:"Good string ©"]; NSLog(@"String:%@",string); return string; } @end // Protocol @protocol MyKeyProtocol - (void)lock; - (void)unlock; @end // Class that implements a protocol @interface MyClass2 : Object { } // Protocol methods - (void)lock; - (void)unlock; @end