@property @synthesize

You asked for simple terms:

@property declares a property in your
class header

@property (nonatomic, retain) NSString *myString;

@synthesize creates your setter and
getter for your property (accessor
methods)

Without synthesize you have to write
your own setter and getter
implemention, like getMyString or
setMyString (capitalize the first
character of your property)

Sam: Just an advice: http://www.cocoadevcentral.com/d/learn_objectivec/ is a pretty solid resource to learn about basics like properties.

Good Luck!