In a right cylinder, the two parallel and congruent bases need not be circles.
Property
A right cylinder whose bases are circles is also called a right circular cylinder.
If the bases of a cylinder are circles, then the cylinder is said to have circular bases.
Examples
Right circular cylinder and right cylinder with an non-circular base:
Formulas
The lateral area \(A_{L}\) dof a right circular cylinder of radius r and height h is given by \(A_{L}=2\pi rh\), that is, the height multiplied by the circumference of the base.
The total area \(A_{T}\) of a right circular cylinder of radius r and height h is given by \(A_{T}=2 \pi rh+2 \pi r^{2}\), that is, the sum of the lateral area and the area of the two circular bases, or \(A_{T}=2 \pi r(h+r)\).
The volume V of a right cylinder of radius r and height h is given by \(V=\pi r^{2}h\).