Grenade launchers fire two types of grenade, Fragmentation and Anti-Tank. Grenades, naturally, are less powerful than missiles, but are easier to fire on the move. They can also fire more exotic types of grenades, as below, though these are not standard issue, and need to be loaded for firing individually.
Anti-tank (or AT) grenades are meant to be used against hardened targets such as armoured vehicles or buildings, etc. They are designed to implode, rather than explode, as is usually the case with grenades.
EMP grenades (or scramblers) are grenades that explode with a powerful EMP effect, destroying electronic systems and incapacitating vehicles.
The fragmentation grenade is a small hand-held or launcher-fired explosive device meant to hurl shrapnel in all directions. They are usually either disc shaped with a button in the center that can be pressed repeatedly in order to determine how long until it explodes, or a small egg shape.
A hallucinogen grenade fills its area of effect with an invisible hallucinogenic gas, causing anyone breathing it in to experience visions which may have various effects on them, from nothing to running from the field screaming.
Photon Flash Flare
Photon flash flares explode with a tremendously powerful flash of light, which will temporarily blind anyone without protection in its area, and may even effect those with protection.
Plasma grenades explode to produce a ball of plasma that covers an area. This will shrink as it uses the available energy in the surrounding area.
This grenade emits infra-red bafflers and broad-band spectrum electro-magnetic radiation in addition to smoke, to blind not only normal eyesight but also artificial sight aids.