MMM is for Marines, Marauders and Medivacs combo of Terran strategy. Unlike the mech build of terran, MMM move quickly and easily. They can hit your enemy in different places at once.
The advantage of this specific strategy is because these units work together perfectly with each unit. Stim Packs are very effective that allows marauders and marines to be strong in combat, then the Medivacs gives support, healing them after they go with their stim pack. One more thing, you can then concentrate on upgrading your infantry at Engineering Bay, and for each upgrade, this will benefit your marines and marauders.
This 3M strategy also lets you build up your infantry into Medivacs and then drop them in some location at your enemy’s base. You can do this at your enemy’s mineral lines, or some other spots to split up your opponent’s army.
Then marauders are good support unit, which can turn the tide of the game if used correctly with the correct combinations. Also, be on the look out for air units and concentrate fire on armored units to do maximum damage as much as possible.
Here is a basic MMM Build Order:
1. Get 10 SCV cap, then make supply depot.
2. Continue to make SCV, then on 12 cap, go with Barracks, and do non-stop scv pump. Also get gas and have the orbital command after the barrack is built.
3. On 16 Cap, build your 2nd depot, then put tech lab on your barrack, then pump out those marauders
4. Build the second barrack, get the MULE when orbital command is done, and produce reactor on your 2nd barracks. Pump marines and marauders continuously.
5. You can then build factory, then starport to make medivac, or probably siege tank.
6. When you have the MMM combo, it’s time to go for a push on your enemy.