A calender is a series of hard pressure rollers used to finish or smooth a sheet of material such as paper, textiles, or plastics. Calender rolls are also used to form some types of plastic films and to apply coatings.[1] Some calender rolls are heated or cooled as needed.[2] Calenders are sometimes mis-spelled calendars.

Calender process
Calender at end of paper machine
Old calender machine
Threading paper through calender rolls, 1941
Calender rolls for milling and mixing rubber
Calender machine for electrode pressing in Lithium-ion battery manufacturing