Light machine guns
Light machine guns are very similar to assault rifles and belong to the small guns category. What sets them apart from assault rifles and medium machine guns is the fact that they have the selective fire capabilities of assault rifles, meaning they have a single shot fire mode, while also having a burst fire mode to deliver sustained suppressive fire.
In practice, this means that LMG's have a single shot mode that is a bit slower than that of an assault rifle, but offers more range and somtimes more damage. Their spread and 1hex parameters sit between that of the AR and the MMG, making it much more viable to hit single targets with single shots rather than bursts. They have a low, but noticable chance of applying suppression as well, though it requires a skilled shooter.