Images formed in Concave and Convex mirrors
In case of curved or spherical mirrors, either the inner or the outer surface of the spherical section has a silver coating that creates a reflecting surface.
The mirror is concave if the reflecting surface is on the inner side; if the reflecting surface is on the outer side, then the mirror is a convex mirror. All light rays coming from any object placed in front of the mirrors will be reflected according to law of reflection. To obtain an image of an object placed in front of a concave or convex mirror, the direction of only the three light rays emanating from the object is sufficient to determine the position and size of the image.
Depending on where an object is placed in front of a concave mirror, the image formed can be inverted/erect, enlarged/diminished and real/virtual. The distinction between real and virtual images is that when an image formed is on the side of the mirror as the object, we say that the image is real and when the image formed lies behind the mirror, we say that the image is virtual.
A concave mirror can produce virtual images as well as real images, the magnification produced by a concave mirror can be either positive or negative. A convex mirror, however, forms only virtual images, so the magnification produced by a convex mirror is always positive.