The "Male" tank was a category of tank prevalent in World War I. As opposed to the five machine guns of the female version of the Mark I tank, the male version of the Mark I had a QF 6 pounder 6 cwt Hotchkiss and three machine guns. By the end of World War I, tank technology was advanced enough for tanks to be both male and female.
The original article can be found at Male tank and the edit history here.