Assault class is the classification for people who use any form of assault rifle in a rather general manner. An assault rifle is defined as a rapid-fire, magazine-fed automatic rifle designed for infantry use. To understand this definition, you must also understand that infantry is defined as soldiers marching or fighting on foot. This basically means that assault class is any general use automatic rifle being used for general fighting purposes. These players are typically on the front lines of the fighting.
There are many guns that are defined as assault class rifles, but the most common gun that is basically the poster child for the assault class is the M4. It is the most generally used adaptable gun. Assault class guns are typically highly adaptable with large ammo capacity and a medium length barrel. Typically, they have many rails so they can hold a wide variety of attachments so they can change for the environment.
Another popular assault class rifle that defies expectations is the Ak47. Normally, these rifles have few, if any rails. This makes them far less adaptable. They also normally have fixed stocks, most assault rifles have adjustable stocks. They do, however, have medium length barrels.
One of the more modern assault rifles is the G36C. This gun has a long top rail but smaller side and bottom rails normally. They typically have collapsible stocks which make them easier to move while not allowing for adjustments. They also have built in carrying handles on the top to allow for easier moving of the rifle.
These guns are designed to have longer range capabilities than CQC guns, yet not as far and the DMR class. They are general use rifles with high adaptability ratings.
The assault class depends highly on chest rigs and plate carriers. These allow the player to carry extra ammo as well as other gear such as flashlights, knives, and grenades. Plate carriers are body armor vests that can be customized. They have what is called MOLLE straps which allow for MOLLE compatible attachments to be mounted anywhere on the rig.
Many assault class players use helmets. Most of these are also highly adaptable to be able to have many different forms of attachments on the helmet. The helmet in the image shown has a communication headset as well as a flashlight attachment.
Players also rely heavily on whatever form of camouflage is needed. One of the most common forms is multicam. Multicam was designed to be a form of camouflage that can hide people in nearly every environment. It has a wide variety of colors in a pattern that allows for the colors to blend in with woodlands, deserts, and even mountain terrains. There are also other popular and effective forms of camo such as ACU which is a form of digital camo which only recently became popular.