Can not be used in initWithString NSDate

NSDate * toDate = [[NSDate alloc] initWithString: @ "2000-10-10 12:00:00 -0500"];
Errors are
No Visible @ interface for 'NSDate' declares the selector 'initWithString:'
This is why, seeking Daniel explained.
Reply:
Wood has this interface. Look api, or add their own.
Reply:
Without this interface, -!

NSString * a = @ "asd";
NSData * data = [a dataUsingEncoding: <# (NSStringEncoding) #>];

Your quest is not this? string into data