Fragmentation Grenades/Mines
Fragmentation Grenades deal heavy damage to everything close to their explosion site. They’re lethal, loud, and are certain to trigger an alert if there’s anyone guarding the area who isn’t 100% dead.
To be really mean, use a Mine Template with a Frag Grenade and place it around a corner. Make noise nearby to lure a guard over, then hide as they approach. It’s overkill, and it isn’t fair, but it is fun.
Concussion Grenade/Mines
These are non-lethal weapons. They give you the ability to stun your targets, who are blinded for a moderate period, giving you a chance to hit them with Takedowns, Stun Gun shots, or other non-lethal weapons.
Gas Grenade/Mines
Gas Grenades knock out their victims, leaving them alive, but incapacitated. They cover a substantial area with their disabling effects, but it takes more time for them to operate compared to Concussion Grenades.
If you have a Rebreather, these weapons let you gain a huge advantage in your fights. Your enemies collapse unless they have helmets (gas masks) or are robotic in nature.
EMP Grenade/Mines
EMP weapons temporarily disable inorganic targets and Augs. Use these to help destroy drones, robots, and guards that are using some of the more powerful abilities (Invisibility, Titan, etc.). This also works against Exo Suits and a certain boss to disable them briefly while you go in with a Takedown.
Smoke Grenade/Mines
Smoke Grenades don’t hurt anyone, but they provide an obscuring effect so that you can cross an area without taking much fire from enemy combatants. Used outside of combat, these devices get people’s attention, but don’t always trigger an alarm. Make sure no one sees you throwing the grenade and it’ll be fine.