Removable orthodontic appliances can be inserted and removed by the patient. They are used for minor tooth movement like arch expansion or retention after fixed treatment. The appliances consist of active components that produce tooth movement, such as springs and screws, as well as retentive components like Adams clasps that help hold the appliance in place. Removable appliances are easy to fabricate and adjust, require less force than fixed appliances, and are more aesthetic and cheaper than fixed options. However, they rely on patient cooperation and are only suitable for limited tooth tipping movements.