ARCHERY SIGHTSArchery sights are a critical component to any compound bow used for hunting. An archery sight matched to your compound bow gives you a point of reference not only on the game animal or target, but in your form. If you use a sighting system that includes an archery sight and a peep on your bowstring you have 2 points of reference to ensure your form is consistent from one shot to the next. It is this consistency that yields accuracy in archery and bowhunting.
Sight pins.
Most archery sights on the market today include a fiber optic pin design that helps create very bright pins in low light conditions often encountered by hunters. The fiber optic technology draws light through a coil or similar orientation of fiber optic material that is one piece right to the tip of your sight pin where that gathere dlight is delivered. These pins make it very easy to see your point of aim in low light conditions and can give you a real edge at longer distance. Speaking of longer distances, you can even select pins that are smaller in diameter to give you a better view of the target at long range. The archery sights will also be very adjustable allowing you to make very small, and measurable changes to your sights to affect arrow point of impact. As an aside, when you finally get your sight set it's a good idea to take a small marker and make a few small dots on the site to mark the alignment of the adjustments - if the sight gets bumped in the field you can quickly check these marks to ensure your sight has not moved.
How much adjustment do I need?
Beyond the pins the adjustability of the archery sight is the most important feature. It is really a personal preference and cost is typically a big factor here. I prefer a workhorse type sight that remains bright in low 
light conditions. I don't want crazy adjustments, levels, lights and other gadgets to get in the way of a basic sight picture and functionality - one more thing to get caught on a limb or bush. I also use a minimum of pins on my archery sight to keep it simple at the moment of truth. As a bare minimum you will want a sight that has a vertical and horizontal adjustment operated by a single allen screw.
Bells and whistles.
When I bought my Mathews Reezen the bowshop suggested a sight by Toxonics, but when I looked at the complexity of the sight, and the pricetag, I opted for the Solid Gold Workhorse model. Solid construction, very adjustable and nice bright pins for half the price of the Toxonics archery sight. In practice I have been very pleased with the sight, and in low light shooting the pins absolutely glow. This archery sight does not have a level, additional light, or other bells and whistles. These items can help make you a better shooter by keeping your form more consistent, but they come at a cost and can make things confusing when a deer walks into range.
Your sight pins can be set at 20 yards, 30 yards, and 40 yards which is pretty common for most bowhunters, Archery sights are made to accommodate more pins, but when a deer walks under your stand it is helpful to have just a few choices rather than a half dozen. In reality, most bows will shoot pretty flat from 10 to 25 yards. With practice and a well positioned archery sight you can make most shots that will present themselves in the woods.