The frag grenade is your standard timed explosive for soldiers on foot. Throw it behind cover to flush out a group, and watch out for FND Assaulters throwing theirs back at you.
Throw it into a group or behind the cover an enemy is using. Since it is timed, bounce it off walls or lob it high to land it where you want. Switch to dynamite or C4 for vehicles.
When an FND Assaulter throws a grenade at you, move away from it straight away. Staying in cover is how you get caught by the blast.
Bait
Bait is a chunk of meat you throw to draw predators to a spot. Toss it near FND soldiers and let the local wildlife do the fighting, or use it to bring out animals while hunting.
C4
C4 is a remote-detonated explosive you place and trigger when the moment is right. It is your best tool for setting traps on roads, wiping out parked vehicles or blowing up a target without being nearby.
Dynamite
Dynamite is a timed explosive built for wrecking vehicles rather than soldiers on foot. Throw it under an armored car or tank and get clear before the fuse runs out.
EMP Grenade
The EMP Grenade shuts down vehicles, cameras and alarms in its blast. Throw one before you sneak into a base to blind its security, or stop a vehicle dead in its tracks.