The Eye of Providence (or the all-seeing eye of God) is a symbol showing an eye often surrounded by rays

Ray (optics)

In optics, a ray is an idealized narrow beam of light. Rays are used to model the propagation of light through an optical system, by dividing the real light field up into discrete rays that can be computationally propagated through the system by the techniques of ray tracing. This allows even very...

 of light

Light

Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 or a glory and usually enclosed by a triangle

Triangle

A triangle is one of the basic shapes of geometry: a polygon with three corners or vertices and three sides or edges which are line segments. A triangle with vertices A, B, and C is denoted ....

. It is sometimes interpreted as representing the eye of God watching over humankind (or divine providence

Divine providence

In Christian theology, divine providence, or simply providence, is God's activity in the world. " Providence" is also used as a title of God exercising His providence, and then the word are usually capitalized...

).

In the modern era, the most notable depiction of the eye is the reverse of the Great Seal of the United States

Great Seal of the United States

The Great Seal of the United States is used to authenticate certain documents issued by the United States federal government. The phrase is used both for the physical seal itself , and more generally for the design impressed upon it...

, which appears on the United States one-dollar bill

United States one-dollar bill

The United States one-dollar bill is the most common denomination of US currency. The first president, George Washington, painted by Gilbert Stuart, is currently featured on the obverse, while the Great Seal of the United States is featured on the reverse. The one-dollar bill has the oldest...

.
Imagery of an all-seeing eye can be traced back to Egyptian mythology

Egyptian mythology

Ancient Egyptian religion was a complex system of polytheistic beliefs and rituals which were an integral part of ancient Egyptian society. It centered on the Egyptians' interaction with a multitude of deities who were believed to be present in, and in control of, the forces and elements of nature...

 and the Eye of Horus

Eye of Horus

The Eye of Horus is an ancient Egyptian symbol of protection, royal power and good health. The eye is personified in the goddess Wadjet...

.