Capsules are solid dosage forms that enclose one or more active ingredients within a soluble shell. There are two main types: hard gelatin capsules made from dried ingredients within gelatin shells, and soft gelatin capsules primarily used for oils. Capsules are manufactured through a process involving dipping pins in gelatin solutions to form shells, drying, stripping from pins, trimming, joining halves, and polishing. They are filled using machines that orient, fill, and rejoin capsule halves through various station processes. Capsule filling machines range from manual to industrial automatic models with capacities of thousands to hundreds of thousands of capsules per hour.