Cylinders have just one wall and are curved relative to a horizontal plane.
Cylinders can also be described as Curved Panels.
Most cylinders parts are more than one brick tall. Just like Panels, some have studs on the top and some do not.
680131×2, Ø2 ½-Circle Brick
876171×5½ Cylinder w/ Handle
731113×3×2 Round w/ Recess, 4-Studs, Axle Hole
309872×2×5, Ø4 ¼-Cylinder
245932×4×2, Ø4 ½-Cylinder
62592×4×4. Ø4 ½-Cylinder
859412×4×5, Ø4 ½-Cylinder
879263×6×6, Ø6 ½-Cylinder
35353×3×2, Ø6 ¼-Cylinder
40414×4×3, Ø8 ¼-Cylinder
305624×4×6, Ø8 ¼-Cylinder
603733×3×5, Ø4 ¼-Cylinder w/ 2-Bows