"Image" in mathematics means that there is a certain correspondence between elements in two groups, that is, "one-to-one correspondence". For example, two positive integer sets A and B, if there is a function f: A → B, so that any a∈A has a unique b∈B and f(a)=b, then we say that there is an image between A and B. The concept of image is one of the most important basic concepts in mathematics, which provides a solid foundation for many theories and methods in mathematics.

Image can also refer to some geometric concepts, such as reflection of image. In geometry, the reflection of an image refers to the reflection of an object on a mirror. The image reflected by the plane mirror is an image. The concept of such images is widely used in geometry, optics and computer graphics, which provides a powerful tool for us to explore the physical and natural world.

In mathematics, there is also a common image, which is the function image. Function image refers to the set of values of elements in the corresponding domain after function transformation, that is, the set of values of function image. For example, the function f(x) = 2x, just like all positive integers. The concept of image is an indispensable concept in function theory in mathematics, which helps us to understand the relationship between functions and variables and provides a powerful tool for us to solve practical problems.