There are many types of Nerf ammunition that have been used over the years.
Nerf Ballistic Balls were the first kind of ammunition used in Nerf guns. They have steadily decreased in popularity because of the relative inaccuracy and limited range. Older Nerf balls are softer and yellow, while newer ones are firm and green. They can be replaced by foam golf practice balls, which are cheaper in bulk. Currently available blasters that use Balls as ammunition are the Buzz Saw and the Reactor. Blue and purple Ballistic Balls have been sold in the past.
The Bungee Ball was a Ballistic Ball with a bungee rope tied to it. It is a very rare piece of ammunition, so it needs to be handled with care if owned. Can sell for high price on eBay. they do not work well and break very easily.
Only featured in the SuperMaxx Ball Shooter, the Larami Ball has become the rarest ballistic ball variant. It is made of plastic, not foam like the other variants and could actually hurt when fired. Extremely rare, fakes can be made so don't try to go on eBay and find a real one.
Arrows are longer Nerf projectiles with fins on them, which were used in guns like the Bow 'n' Arrow. However, the original arrows were 11" long and had straight fins, while all arrows released with the Big Bad Bow and after have been 9" and have had angled fins to promote spin and increase stability since they are not front-weighted. They, too have decreased in use, although guns that fire arrows are still produced, such as the Big Bad Bow and the Big Salvo.
Aero Gliders are Nerf arrows with longer sides than normal. They are pretty much the same, but glide through the air longer than any other variant of arrow.
Missiles were a wider and shorter version of arrows which were used in some early Nerf guns. They were extremely accurate and had poor range. No Nerf Missile launching guns are produced anymore, on exception for the Titan AS-V, which uses a much more accurate and larger version of Missiles.
Darts are the most commonly used Nerf ammunition. There is over 7 variations from different Nerf products.
Nerf Mega Darts are large, wide darts with hard rubber tips and are roughly 5/8-inch in diameter. They were the most popular type of Nerf ammo until Air-Powered Nerf guns started to become popular. Some current guns that fire mega darts are the older Tech Target Guns and the Transformers Blasters.
Airtech Jet Squadron Jets were exclusive to the Airtech Air Jet Squadron. They are pretty much a mixture of a Mega Dart and an Arrow. They were quite rare and tiny, so they can sell for a high price on eBay.
Larami Darts were a type of ammunition introduced by Larami with their SuperMAXX line of toys. They are relatively as wide as a mega, but as short as a micro and can be fired from most barrels.
http://www.captainslug.com/nerf/wiki/ammo/micro1.jpg http://www.captainslug.com/nerf/wiki/ammo/micro2.jpg http://www.captainslug.com/nerf/wiki/ammo/micro3.jpg http://www.captainslug.com/nerf/wiki/ammo/micro4.jpg
Known as Rip Rockets when first used, Nerf Micro Darts are thinner, shorter versions of Nerf mega darts and are roughly 1/2-inch in diameter with a foam body that is 2-1/2 inches long. They normally get superior ranges to Megas and are the current most popular type of dart used by Nerfers. Most guns produced today fire micros. There are many types of micro darts.
The Dart Tag Dart features a velcro tipped head, to stick to dart tag vests. The dart tag dart can be fired out of a Nite Finder EX-3, and all other nerf dart tag guns. It can not be fired from the Maverick REV-6.
Glow Darts are regular Micro Darts with glow in the dark paper stuck onto them. They are not wildly used as ammunition by Nerf fans and only the Firefly REV-8 actually supports the use of the glow in the dark paper.
Pen Darts are the tiniest type of Nerf dart to date. They were only included with the Pen Blaster and can be quite hard to find. They are sometimes referred to as "Mini Darts".
The Sonic Micro Dart is a dart that whistles when shot at long to medium ranges. The whistle noises are created by a small opening at the top. However, this opening makes the dart inaccurate compared to other darts. For this reason, most Nerf fans use other darts.
The Streamline Dart is the only Nerf dart that is compatible with Clip System blasters. Streamline Darts are compatible with any type of Clip. They are also lightweight, with no weighted tip which makes them fly awkwardly in the air. The tip of the dart is similar to the the Sonic Micro Dart.
The Whistler Dart is a dart that whistles when shot. The whistle noises are created by a small opening at the top. This opening, however, makes the dart inaccurate compared to other darts. For this reason, most Nerf fans use other darts.
Grenades are home-made hand-held weapons for Nerf that are very simple to make and can be made through various methods. Though most of the time they are made by strapping several Streamline Darts together with an elastic band. The effect is supposed to confuse the enemy.
Stefans are homemade darts that are normally made from Foam Backer Rods (Caulk Saver), hot glue, and some kind of weight. They were invented by Canadian Nerfer Stefan Mohr and are made in five sizes, nanos (3/8 in.), micros (1/2 in.), megas (5/8 in.), jumbos (3/4 in.) and mongos (1 in.).
Very poor range and accuracy. Never used at wars for obvious reasons. Are fired from guns such as the SuperMaxx Disc Shooter and many cheap disk shooters, along with electronic disk shooters.
Gyro Missiles are tiny, Micro Dart-like bullets that have a hard cap on the end of them. They were only featured in the Gyro Strike blaster and can hurt when fired. They have poor range, so hitting your mark is harder than it seems.
Shells are not a type of ammunition, but rather are a short length removable barrel used in many Buzz Bee brand blasters. Made of plastic, they are loaded with the dart and become a barrel. Shells are impractical because they double reloading times.
Included with the Disk Shot set to be used as targets that are ejected into the air from the Disk Launcher. Have not yet been used as ammunition but may be once the launcher is modified.
Triple Torch Arrows are pretty much the same as any other arrow except they have fake "blades" or gears at the side of them. This makes them slightly less accurate, however. These are only good at making you look cool when you fire them.
Only featured in the Zap Snaps, which is already rare, from 1992 the Zap Snaps Rocket might be the rarest Nerf ammunition out there. Little is known about it, apart from the fact that it has poor range.
Short-lived and rare ammunition native to only the Koosh Vortex line that has incredible range when used indoors. Doesn't see much use due to its rarity and the fact that its horribly inaccurate when used outdoors. Its low velocity makes it a victim to drifting in even the slightest breeze. Came in two sizes, the larger size was orange and the mini was green.
The Spinfire Rings were an advanced version of the standard Koosh Ring. They worked best indoors, and were practically useless outside. They were slightly bigger and were coloured orange. They were only made for the Vortex line from Koosh.