Tablets are familiar – formed by putting powdered ingredients into a mould and applying pressure. Tablets are simple and can be made in almost any size.
Capsules are made by putting powder into one half of an empty capsule then placing the other half of the empty capsule into place over the first half. Capsules are generally smaller, and because they are smooth, easier for some people to swallow. They are also useful if has ingredients have an unpleasant taste.
Softgels are soft capsules used primarily for liquid ingredients. The capsule is partly formed in a mould, the ingredients injected in and the mould is then closed to form the capsule.