Cylinder mowers feature vertically rotating blades that can cut extremely close for that classic 'manicured lawn' look. While they're perfect for very even lawns, they're not so good for more irregular grass areas. Rotary mowers, on the other hand, have horizontally-orientated blades: the finish isn't quite so good, but the mowers are more tolerant of lawns with rough patches, slopes and - dare we say it - weeds and moss.