Hybrid contact lenses are designed to provide wearing comfort that rivals soft or silicone hydrogel lenses, combined with the crystal-clear optics of gas permeable lenses. It usually takes some time for your eyes to adjust to gas permeable lenses when you first start wearing them, but after this initial adaptation period, most people find GP lenses are as comfortable as hydrogel lenses. GP contacts often provide sharper vision than soft and silicone hydrogel contacts - especially if you have astigmatism. Since their introduction in 1978, gas permeable contact lenses have essentially replaced nonporous PMMA contact lenses. Because they are permeable to oxygen, GP lenses can be fit closer to the eye than PMMA lenses, making them more comfortable than conventional hard lenses. Gas permeable lenses - also called GP or RGP lenses - are rigid contact lenses that look and feel like PMMA lenses (see below) but are porous and allow oxygen to pass through them. Introduced in 2002, silicone hydrogel contact lenses are now the most popular lenses prescribed in the United States. Regular hydrogel lenses and allow even more oxygen to reach the cornea. Silicone hydrogel lenses are an advanced type of soft contact lenses that are more porous than PMMA lenses typically took weeks to adapt to and many people couldn't wear them successfully.

The only alternative at the time was hard contact lenses made of PMMA plastic (see below). Introduced in the early 1970s, hydrogel lenses made contact lens wear much more popular because they typically are immediately comfortable.

These lenses are very thin and pliable and conform to the front surface of the eye. Soft lenses are made from gel-like, water-containing plastics called hydrogels.

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