The Basics

Introduction

This section will provide you with information that can be used by any race. A rush is still a rush no matter who uses it, so some strategies will apply to everyone.

Terms (Starcraft Jargon)

Unit

This word is incredibly tricky to define. You will hear it thrown around all the time by advanced players, but if you asked any of them to define it, they would almost always be stumped. The best definition I could come up with is: "A person, creature, or machine or group of people, creatures, or machines that is capable of acting independently."

Take this marine

It is a single person in a suit of armor. Since he is capable of moving around by himself, he counts as one unit. Now take these Zerglings.

 If they had to move in sync, they would be considered one unit. However, even though they were born out of the same egg, they can move independently of each other, and as such are two separate units. Finally, take this Carrier.

This counts as one unit, despite having over 100 Protoss running around inside it. Why? Because the Protoss work as a group to make the carrier move. Because the Protoss inside the carrier are dependent on each other, they don't all count as separate units.They make the carrier move as a group, and because they are independent of other carriers (containing other groups of Protoss), the carrier as a whole counts as one unit. (Now you see why the word unit is so hard to define)

Fog of War

if you look at a map in any standard Starcraft 2 game, you will see that part of it is grayed out. This is the fog of war. it means that you cannot see anything going on in the terrain underneath it. You can remove it by putting a unit or structure near the area you want to reveal, or if you're Terran using a scanner sweep from the orbital command. Scouting is all about clearing the fog of war.

AoE

Area of Effect, it means an attack damages the target and everything around it.

Harass

A single unit or a small group of units that is very fast and mobile performing a quick attack on an enemies resource gathering location, then disappearing before a defensive force shows up. it is used to damage the opponents economy, and may result in a victory if done well in the early game.

Backdoor

A vulnerable/entrance point in an enemies base that is not the main entrance, it is used to drop spies or perform sneak attacks. Obvious backdoors include areas in your base that are covered by the fog of war, and extra ramps leading into a resource location. A less obvious backdoor is anywhere in your base that doesn't have air defenses, and isn't frequently on your screen. A remote corner that doesn't have anything that needs direct supervision in it is a backdoor because you don't look there very often.

Main Strategy Types

For some of you, the example I used in the introduction won't make any sense because you don't know what a rush is. This section will fix that.

1. Rushing

Rushing is the hit-hard-and-fast strategy. When you rush, you build a few simple units really fast, and "rush" them into the enemies base in hopes of catching your opponent off guard. If done fast enough, your opponent   won't be strong enough to repulse you, and you'll rip his base apart without any resistance. This gets you a quick victory, while your foe is still wondering, "What the **** just happened?" Zerg players love this one.

2. Booming

Booming is the build-up-your-economy strategy. When you boom, you make your workers and expansions a top priority. You let the other guy do his thing while you put all your effort into getting as many resources as possible. you then spend all those resources building a massive army that can squish anything that gets in its way. Protoss excel at this.

3. Turtling

Turtling is the I-dare-you-to-get-through-my-defenses strategy. When you turtle, you wall yourself off from the rest of the map, and try to become as tough as possible. You can then run your operations from inside your impenetrable fortress. Nobody turtles like a Terran.

Rush or Turtle, then Boom

While these three strategies should have a rock-paper-scissors effect on each other, that is not actually the case. In the early game (explained below), you either rush or turtle. If you rush, you are vunerable to other rushers, and they to you. If you turtle, you are immune to rushes, but can't secure an early victory. turtling almost garrentees survival, but at the same time makes sure that the game lasts much longer than if you rushed. Everyone booms after they turtle or rush because if they don't, your oppenent will walk all over you.

Game Stages

For those of you who don't know, there are three stages to each game: Early, Middle, and Late. I will refer to these stages regularly throughout the the rest of the guide.

Early Game

The early game is the first 10-15 minutes. In that time, you build up your first base, get basic troops, prepare to rush or be rushed, and scout the map. Most combat in this stage is simple raiding, trying to slow down your production, or an attempt at a quick victory.

Middle Game

The middle game is when the map and your capabilities start to open up, and encompasses minutes 15-30 or so. You get more powerful ground troops and basic airborne units, start getting expansions, start upgrading, and engage in larger battles and sieges. Most games end near the end of this section.

Late Game

The late game is the most interesting part, the most dangerous part, and is rarely achieved. This section can last for hours. In it, you'll get your hands on the most powerful ground and air units, spread your influence over large portions of the map, max out your upgrades, and built up your expansions enough that having your main base wiped out will no longer kill you. By this point, the victor has almost always been determined, and is just doing the mop-up.

One man army

When most of you think of a one man army, you see Tychus driving the Odin. What I mean by that phrase, however, is an army that is composed of only one troop type. This is a favorite among new players because it applies to the KISS philosophy, "Keep It Simple, Stupid." However, most units make poor one-man-armies, so I'll tell you which ones can actually pull it off:
1. Vikings
2. Marines
3. Thors
4. Battlecruisers
5. Stalkers
6. Archons
7. Void Rays
8. Carriers
9. Mutalisks
10. Hydralisks
I'll go over what to do with each unit on their respective race pages. Notice that all of these units can hit both air and ground. That is not a coincidence. Each of these armies has to be able to deal with anything the enemy throws their way. That's why air-to-air and ground-to-ground units make bad one-man-armies.
Examples of bad one man armies:
roaches
immortals
reapers