A printer includes a platen roller, a printer main block including a print head that prints information on recording paper placed between the print head and the platen roller, a movable-blade block including a movable blade, a fixed-blade block including a fixed blade, a feed driving block including a feed driving motor that rotates the platen roller to feed the recording paper, and a movable-blade driving block including a movable-blade driving motor that moves the movable blade. The printer main block, the platen roller, the movable-blade block, the fixed-blade block, the feed driving block, and the movable-blade driving block are detachably attached to each other to form the printer that includes a function to cut the recording paper with the fixed blade and the movable blade.