Bits and Pieces: Eyeglass Parts

A full metal frame with decorative temple.  This type of temple bends down behind the ear and is most common.
Model: Tura 694 by Tura

Quite often I get a frantic phone call from someone who's broken their glasses.  Their tangable chaos is in pieces in their hands, and they are wondering how they are going to get to work, or even to my office, and whether or not the doohickey that came off of the thingamajiger is repairable.  Me being a helper, I want to be able to tell them whether or not to worry, but too many times people just don't know the proper name of the parts of their glasses, and it becomes a little "sticky" trying to "diagnose" problems over the phone. 
First of all, I'm going to preach.  ALWAYS have a back up pair of glasses.  It is not comfortable to get through your day when you can't see as well as you know you should.  Also, if your drivers license indicates that you need corrective eyewear for driving and you are caught without, that is only going to make a bad situation worse.
So lets talk frame parts. 
Often miscalled 'bows', 'bands', arms, feet,legs, 'riders' and even 'kickstands', the part that extends from the front of the glasses along the side of your head and over your ears is called the TEMPLE.  Many of the fitting issues involved with eyeglasses can be solved by adjusting the temples.  Temples come in many different styles and materials, some go straight back behind the ear and hug the head, but most bend down behind the ear to help the glasses to stay put. 

this type of temple does not bend down behind the ear
Model: Smarter by Jee Vice

The FRONT, then, is the entire front piece of the frame, including the eyewire, which holds the lenses in place, and the bridge/nosepads.
 Those little pads that cushion the weight of the glasses on your nose are called NOSEPADS, and they are attached to the NOSEPAD ARMS.  They also come in many shapes, sizes and designs.  Some snap into the arm, some screw into the arm, and some are clamped in. Many people mistake the nosepad adjustment is the culprit when their glasses are crooked or are sitting on an angle, but truly the only main functions of the nosepad are to cushion the nose, and the make the glasses sit higher/avoid slipping down the nose.  They do need to be properly adjusted in order to feel comfortable, and as the nosepad arm is the most susceptible to breaking during a do-it-yourself repair, it's best to see your optician for a good adjustment.

Nosepads are generally found on metal frames.

Not all frames have nosepads.  If you choose a frame that is made of plastic, you will generally not have nosepads to contend with.  The pros of not having nosepads?  It distributes the weight of the glasses evenly across the nose, which is more comfortable for most people.  The cons?  They are less adjustable overall.
Another important part of your glasses is the HINGE.  This is the area where the temple folds.  There are many different types of hinge including:

This durable double hinge has a patended design that compresses the spring instead of stretching it.  These hinges are far more durable than the standard single-barrel hinge
Model: Elasta 7171 by Safilo Group

This is a very uncomplicated hinge.  There is no spring, it simply opens and closes.
Model: Aero F12 by Match Eyewear

This is a single-barrell hinge, the most common of all types.  They do absorb some of the impact of eyeglasses, but the springs inside aren't designed to last more than a year or two.

A completely hingeless frame.  These are generally only found on drill mount frames, and do not hold up well.

Here another simple hinge.  It simply opens and closes, no spring.  These generally last a really long time, but in this case, it makes the frame very un-adjustable.

So what's my recommendation in the way of hinges?  If you are a person who replaces your glasses every 1-2 years, choose whichever style is most comfortable.  If you like to wear your glasses for longer than that, you should stick with springless types of hinges.  Your glasses will generally hold up much better over time.