If you notice things not going your way, don't hesitate to fall back for a minute or two to regroup and hit again when you have a larger ball or Marines. If your enemy is unprepared, this small force can easily decimate his worker line and then his base. As soon as you have 4 Marines, begin marching them over to your enemy base, sending any new ones that build over after them. While they build, queue up a few more SCV's and build 1-2 more supply depots as the become necessary. When you get 150 more minerals, begin a second Barracks. Build your SCV line, plop down your first Supply Depot and once it is done begin a Barracks.

This build is simple to do also, which helps explain why it is so popular. Due to this, Marine harassment can be quite powerful against enemies who don't know the proper way to counter it early on. They are cheap, fast and have a ranged attack which no other starting unit has. It goes without saying that Marines are quite possibly the most useful unit to ever exist in SC2.

Terran players will want to build plenty of SCV's and get their Orbital Command as soon as possible so they can call in Mules and gain Scan access.

Terran players can rely solely on minerals for a very long time, having little need for Vespene until later in the match. You will want to build as many as you can so you can sustain your constant building. There is one thing that never changes for the Terran though, SCV's. Terran excel during these opening minutes thanks to the ease of making Marines. In the beginning minutes of a match, Terran players tend to act very Zerg like.

Starcraft 2 how to play terran