Using Terran 2 Barracks Pressure In StarCraft 2
The 2 Barracks pressure build, also known as the 2 Rax pressure build is a build that is commonly used against the Protoss as a Terran player.
The recommended way to start is to first create a Supply Depot then a Refinery with just one SCV assigned to it, all while continuing to produce SCVs.
At thirteen supply you will create your first Barracks. At sixteen supply you should upgrade your Command Center into an Orbital Command as well as get a second Supply Depot. By the time the second Supply Depot is finished you should start constructing a third Supply Depot. You will then add a Reactor to the first Barracks and start constructing the second Barracks.
Once the second Barracks has been created you will then add a Tech Lab to it and assign another two SCVs to the first refinery. You can now start producing Marines and Marauders from your two Barracks structures while constructing another Command Center. Send out your Marines and Marauders to pressure your opponent while researching the Concussive S[censored] upgrade and then researching the Stimpack upgrade.
You should also construct additional Supply Depots while producing units and workers. Alternatively you may produce Reapers if your opponent decides to create more light units instead of armored units. This would commonly be the case if your Protoss opponent decides to go for a quick Zealot rush. The additional speed provided to the Reapers should allow them to kite such light units with relative ease provided that you keep an eye on them.
If you go for Reapers instead of Marauders you do not need to get the Concussive S[censored] upgrade as early in the game. If your opponent has a sizable amount of light units on the field you may also consider teching to the Factory in order to produce some quick [censored] ions for additional harrassment of your opponent.
There is an all-in version of this build that is also sometimes effective against a Protoss opponent that tries to fast tech to fancier units while working on their economy. This alternative build involves skipping the Command Center in order to quickly tech up to a Starport with a second Refinery being built. Medivacs can then be produced to heal your infantry and SCVs can be pulled off to absorb enemy damage.
This is a game of a tactics. The player has to coordinate their attacks well. They also have to make proper use of military hardware as they tackle their adversaries. Speed and thoughtful actions are called for.