The Orion Nebula includes ionized volumes of gas, associations of stars, neutral clouds of dust and gas, and reflection nebulae. The nebula forms a roughly spherical cloud. This cloud's temperature reaches up to 10,000K. It is more dense towards the center. The different parts of the cloud move at speeds of 10-50km/s with respect to each other. According to the current model, the star Theta Orionis C is at the center of the cloud. That star is surrounded by an ionized region. This region is surrounded by a more neutral, high-density cloud. All of this lies on the perimeter of the Orion Molecular Cloud.
It is one of the brightest nebulae, and can actually be seen with a naked eye, even from a distance of 1,344 light-years away. It is estimated to be 24 light-years across. The visual landscape of this object looks like plateus, mountains, and valleys seen from the Grand Canyon.
Supersonic "bulets" of gas peirce through the dense clouds of the nebula. These bulets are ten times larger than the diameter of Pluto's orbit. They are tipped with iron atoms, which makes them glow with bright blue color.
This nebula is part of a larger region called the Orion Molecular Cloud Cluster, which contains, Barnard's Loop, the Horsehead Nebula, M43, M78 and the Flame Nebula.
The Mayans of South America, drew a fuzzy star in this region of the constellation. In modern times, the first scientist to officially discover the nebula, was Nicolas-Claude Fabri de Peiresc. A Jesuit astronomer, Cysatus of Lucerne, was first to publish a note on it. When Messier was cataloguing the space objects, this nebula was the 42nd object he catalogued, hence the name it is also know as, M42.
This nebula is believed to be one of the most turbulent star forming regions in space, but we really don't know what is going on behind those clouds. The only thing we know for sure, is that this space wonder looks breathtaking.
Sources:
http://nasaimages.org/luna/servlet/detail/NVA2~8~8~11920~112452
http://en.wikipedia.org/wiki/Orion_Nebula