Rigging

Once a model has been created it is necessary to rig it, in essence this means putting a skeleton into the model, this then allows the animator to move it as he so desires. This part of the process is a complicated and delicate one that must be done correctly in order to provide a realistic looking way for the character to move. For example when we move our hands it has affects on our forearms, if a rig is done incorrectly then this won't be the case and whilst it might be subtle, it will affect whether or not the animation feels right. The rigging process includes creating animation handles all over the body, especially the face to ensure that it is malleable for the animator to create any and every facial expression that he/she needs to. The rig is not rendered, so it will often be left sticking out of the model and moved into odd shapes, however it is the position of the model that truly matters. This stage of the process is usually performed by a Character Technical Director, more information about this job role can be found from the link below, but in essence their job role involves ensuring that the model is completed to the desired finish and works perfectly with the rig to ensure that when it is handed to the animators there are no bugs or glitches to overcome that will drastically slow down the process.
http://www.technicolor.com/en/hi/animation-vfx/animation/careers/character-technical-director
At the top of this section is an extremely basic video tutorial showing the very simplest way to rig an object in maya. Naturally there are far more complex steps, but this allows you to see how riggin actually works in practice.