NSArray: - (unsigned) count - (id) objectAtIndex:(int) - (BOOL) containsObject:(id)anObject
NSMutableArray - (void)addObject:(id)anObject - (void)insertObject:(id)anObject atIndex:(unsigned)index - (void)removeObjectAtIndex:(unsigned)index - (void)removeObject:(id)anObject NSDictionary: - (unsigned) count - (void) setObject:(id)anObject forKey:(id)aKey - (NSArray*) allKeys - (id) objectForKey:(id)aKey NSMutableDictionary - (void)setObject:(id)anObject forKey:(id)aKey - (void)removeObjectForKey:(id)aKey To store int, float, long: wrap inside NSNumber object Serializing to/from a file (in plist format): - (id)initWithContentsOfFile:(NSString*)aPath - (BOOL)writeToFile:(NSString*)aPath atomically:(BOOL)flag |