Basic Terran Build

Things to note: Keep your base spread out. Compact bases are nice and all but as Terrans you have mobility, so stop turtling and conquer the map!

Build SCVs until you have your 7th one being made. 7th one comes out and builds a Barrack (NOT A DEPOT). 8th one is being made and once it pops out, it should make a supply depot, your barrack is halfway finished. 9th SCV is made and goes right for minerals. 10th SCV is made, barracks is finished, depot is finished. First sent two SCVs to harvest minerals. Build 1 marine (Dont build more than 1 at a time or it hogs your minerals). When you have the funds (which you should), make your refinary. Make another SCV, this one is made and goes to make your second barrack. Make another SCV. (Note, this entire time your making marines as soon as one is done). The very moment you have 100 minerals, use any resource gathering scv or free scv to build a depot. Refine should be finished so now take another two scvs who are free / resource gathering and shove them into the refine, your priority is gas. By now you should have atleast 3-5 marines or more, both depot made and second barracks. Send your workers that are finished building to the patch. Build more scvs and keep building marines (1 at a time in each building). The next SCV made makes your academy since by now you have a fair amount of gas. After that another depot made by the next SCV, and after that, a factory. Keep in mind, that whenever a SCV finishes building something, it goes to the mineral patch and the newest SCV built makes the next structure. As soon as Academy is finished, make your comsat. Make firebats first, (until each barrack has produced 2 bats, giving you a total of 4). Then get your medics, 2 or 4 is enough. You have your small defense squad and your factory should already be made with a machine shop researching siege mode. (Or Vulture mines if you plan on being defensive and defend yourself and allies while they attack. If its a 1 VS 1 and such, get tanks and stay offensive.). Keep building SCVs, more you have the better, you can never have too many (well...just dont go past the 70+ range in a low money map, might turn ugly).

This is just a basic build, with nothing special about it except that it can handle rushes and it'll get you going. Its the average Terran build which could most likely handle any early situation. As time progresses, remember to continue building more barracks and factories (or starports if you plan on going air) but keep your base and depots spread FAR OUT. For example, if Im playing hunters, My base WILL extend all the way to the center of the map and I'll have troops running all over the place. Hell, if it makes you feel any better, go ahead and expand right into your enemies territory. You have mobility, make the best of it. Also, whenever you attack ALWAYS send marines and ALWAYS send SCVs. Build bunkers right in the middle of the battle! Repair! Thats the nature of a Terran.

P.S. Strongest Terrans utilize marines, medics (with some bats) and Tanks with Air Support such as BCs. YES! If you use all of these your attack seriously hurts since every unit will support each other. BC's dont need to be upgraded but give them Yamato. Upgrade Marines and Tanks however and if you spread your bases out, expansion is not a problem and defense is actually easier than tiny cluster bases. Tell me, whats harder in Hunters? Someone who has their tiny base and expansion or someone who has 7/8's of the map including the center?