Eye of Horus

Designed to resemble the eye of a falcon, this symbol, called the Eye of Horus (or Eye of Ra), represents the right eye of the Egyptian Falcon God Horus. As the udjat (or utchat), it represented the sun, and was associated with the Sun God Ra (Re).
According to legend, the left eye was torn from Horus by his murderous brother Seth, and magically restored by Thoth, the God of magick. After the restoration, some stories state, Horus made a gift of the eye to Osiris, which allowed this solar deity to rule the underworld. The story of this injury is probably an allusion to the phases of the moon as the eye which is "torn out" every month. The Right eye of Horus represents the Sun, and the left Eye of Horus represents the Moon.
The Eye of Horus was believed to have healing and protective power, and it was used as a protective amulet, and as a medical measuring device, using the mathematical proportions of the eye to determine the proportions of ingredients in medical preparations, to prepare medications.