DOTA stands for Defence of the Ancients. It is a mod for Warcraft 3. Since its inception, there have been a number of good DOTA Strategy guides written about it.
Here are 7 DOTA Strategy 101 tips to help you get into the game.
Tip #1 Farming
Farming means killing creeps or neutrals for gold. The more enemy creeps you kill, the more gold you'll receive. Sometimes when farming becomes difficult, player may turn to farming neutral characters for extra gold.
Tip #2 Last Hit
Last Hit means moving in close to hit the enemy creep for gold. Damaging an enemy creep does not provide gold, so its beneficial for a non-ranged character to move in for a last hit to receive this benefit. This also allows you to stay out of range of the opposing team.
Making a last hit requires a feel of the timing to deal direct damage for different characters. You can get a feel of this simply by playing the game often. A good strategy is to keep the thumb on the "ALT" key so that you can readily see the life line of the creeps, and only move in to get a last hit when its life is low.
Tip #3 Hot Key
Hot Key is an essential DOTA strategy. Different spells are tied to different buttons which when pressed will activate the spell. Since battles in DOTA last only a few seconds, clicking on the icons with the mouse is a little slow.
Tip #4 Mouse
Getting a good mouse is important for DOTA. You'll also enjoy the gaming experience more with a good mouse, skates, and mouse pad. Get it from: http://razerdeathadder.blogspot.com
Tip #5 Item Build
Having the right item build will increase the power of your character. Some characters require more health or more speed, or more mana as the game progresses. Knowing the complimentary item build for your character will increase its power and direct damage.
Tip #6 Team Play
In competitive DOTA play, its necessary to play in groups. Public DOTA strategy and Competitive DOTA strategy are different with the latter being more difficult and emphasis on team cooperation.
Tip #7 Mana Required
Always take note of the amount of mana required to cast 2 spells. 1 spell alone will normally not be sufficient to take down an opponent.
Tip #8 Item Cost
By understanding what items need to be built, you'll be able to know the cost and time your return to the fountain. Less trip back to the fountain means more time in the battle field, which translates to more gold and experience for your DOTA character.