Difference between _property and self.property

Question

I\'m slightly confused as to the proper conventions when dealing with properties. I\'ll illustrate my question through an example. So from the example below I know that func

Answer 1

_loan is a variable and assigning a value to it has no particular side effect.

self.loan = self.loan + 250.00 is essentially the same as writing [self setLoan:[self loan] + 250.00] in that methods are called that may do other things than simply set or get the value of a variable. The extra things those methods do depend on whether you write custom versions of them (the setters and the getters) or use @synthesize to create them and, if you use @synthesize, what attributes you apply in the @property declaration.