Lugha inayolengwa: Kiingereza
These are the contact lenses that exist. There are soft lenses and hard.
Today soft contact lenses exist in many choices of types, raw materials, wearing time and various companies.
Common wearing time: daily, bi-weekly, monthly, quarterly, bi-yearly, and various.
Also there are hard contact lenses from various raw materials, which are usually intended to be worn for one or two years.
The difference in the "number" between glasses and contact lenses is because of the fact that a lense is closer to the eye than glasses, and therefore the lense will always be more (+) than glasses.