Xenomorphs are the deadly aliens in the movie Alien. There are many different kinds of xenomorphs but the most well known are the facehuggers, chestbursters, and queens.
The first xenomorph was encountered on planet A6 454 as a facehugger. Later on the chestburster gets loose on the spacecraft Nostromos.
Facehuggers are spider-like creatures that lay their eggs by latching onto a human face and lays the egg in their throat and dies. |
Next, the egg hatches in their throat literally bursting through their chest. The chestbursters then grow up and become a drone xenomorph, drones are expendable, meaning they don't matter to the queen, they are usualy scouts. |
Queens are the leaders, they tell the others what to do, they also lay the eggs for facehuggers to hatch from. |
In the movie Aliens vs. Predator there is a story plot that the Predators came to earth and tought the human race how to build and farm. In return they required sacrificial beings to breed the xenomorphs. They would come back every 100 years to hunt the xenomorphs and claim their "trophies" (which are the skulls of their prey) |
If you are interested in what they look like and the different classes, here is a video I found on youtube.
The creater of this video link Shawn the Prawn