Concave Mirror:- If the inner side of the spherical mirror is reflecting, it is called a concave mirror.
Convex Mirror:- If the outer side of the spherical mirror is reflecting, it is called a convex mirror.
Concave Lens:- A concave lens is thinner in the middle and thicker at the edges.
Convex Lens:- A convex lens is thicker in the middle and thinner at the edges.

Concave and Convex Mirrors and Lenses

Concave Mirrors:
- Concave mirrors are curved inward and can converge light rays to a single focal point.
- These mirrors are used in reflecting telescopes, makeup mirrors, and headlights of vehicles.
- Concave mirrors can produce both real and virtual images.

Convex Mirrors:
- Convex mirrors are curved outward and diverge light rays.
- These mirrors are commonly used in side-view mirrors of cars, security mirrors, and makeup mirrors.
- Convex mirrors produce virtual images that are smaller and upright.

Concave Lenses:
- Concave lenses are thinner in the center and thicker at the edges, causing light rays to diverge.
- These lenses are used in correcting myopia (nearsightedness) and in flashlights.
- Concave lenses can only produce virtual images that are smaller and upright.

Convex Lenses:
- Convex lenses are thicker in the center and thinner at the edges, causing light rays to converge.
- These lenses are used in corrective lenses for farsightedness, magnifying glasses, and cameras.
- Convex lenses produce both real and virtual images, depending on the object distance.

In conclusion, concave mirrors and lenses converge light rays, while convex mirrors and lenses diverge them. Each type has specific applications based on how they interact with light rays. Understanding the differences between concave and convex mirrors and lenses can help in choosing the right optical device for a particular purpose.