See some of this code, the method name in front of a * asterisk, what does that mean?

See some of this code, the method name in front of a * asterisk, what does that mean?
Reply:
Function return value is a pointer

Such as: The return value is a pointer, I do not know whether to say
LZ problem- (NSStrig *) hello {

}

Reply:
Not
I read method is written like this:

NSString * boolString (BOOL yesNO)
{
}
Reply:

The return value is a pointer to NSString method names: boolString
Reply:
In addition to the inside of the type C and NSInteger, other types are use * plus variable names.
For example:
C Language:
int i = 0;
float f = 0.15f;

Objc:
NSString * hello = @ "Hello";
ClassName * className = [[ClassName alloc] init];
Reply:
Domestic book!
Reply:
NSString * boolString (BOOL yesNO)
{
}


- (NSStrig *) hello {

}
Is the same. . . But few saw the first one written