| − | '''Differential geometry''' is a [[geometry]] where differences between [[point]]s are measured using a [[derivative]]. Study of differential geometry requires a firm knowledge of [[calculus]] and [[plane geometry]]. Please note that number theory is ''just'' a theory. | + | '''Differential geometry''' is a [[geometry]] where differences between [[point]]s are measured using a [[derivative]]. Study of differential geometry requires a firm knowledge of [[calculus]] and [[plane geometry]]. |