The current Flag of Iran was adopted on July 29, 1980, and is a reflection of the changes brought about by the Iranian Revolution. The emblem in the center of the flag is a highly stylized composite of various Islamic elements: Allah, there is no god but Allah, and a tulip
The coat of arms of Iran has been placed in the center of the white band which is meant to have multiple meanings, but is essentially a geometrically symmetric form of the word Allah as well as overlapping parts of the Islamic phrase "la ilaha illa Allah" ("There is no god but Allah"), forming a monogram.
There was more info about it, but that is all i wanted to post. The flag is green on top, white in the middle, and red on bottom. The symbol in the center is red. (At least that is how the flag on Wiki looks.)