A gank is simply an ambush attack. It could be against one solitary hero, 2-3, or even all five heroes. One of the main points of ganking is to give you, and your teammates, an advantage of knowing your enemy's position since they did not expect you to come after them. A number advantage (2v1, 3v2, etc.), also known as a power play, can also be obtained in the process. This becomes a perfect opportunity for a surprise attack by moving discreetly alone, or with teammates, with the sole mission to kill a hero or heroes being caught off guard. Moving together in tandem, you will use all possible spells – nukes, disables, etc. – to finish off this hero as quickly as possible. This allows the ganking heroes to move back to their previous positions or back to their lane immediately after the process is finished. Mission accomplished – the farming hero lost money, time, and potential experience.

Different Ways to Gank

Casual Entrapment. A lot of ganks begin as a game of entrapment. You, as a lone hero, scout an area and find an enemy hero, which would most probably try and chase you down; it's human nature to feel superior against another who bids a hasty retreat with your presence. This works to your advantage.

You can set the trap prior to baiting the hero, or make your allies aware of the enemy following your tail. They can come to your assistance to help you dispose of the threat. If he chases you closer to your territory, it will be harder for him to have any support from his teammates, especially if he follows you blindly.

At some point during the game, this kind of gank become too obvious for the experienced player, and will realize that he is going too deep into enemy territory, and back off.

Scouting Jungle. There are some popular “jungling” heroes, which do not play on a lane, but rather kill the creeps in the forest. These heroes should be ganked if possible, since good junglers can make a good amount of money without disturbance from enemy heroes.

Usually, heroes who farm the jungle early game push their hitpoints as low as possible. Catching them at a bad time would spell an early death for such a player. Keep an eye on the lanes – if there’s one less hero, he’s probably killing creeps in the jungle. Use the command –ma (to see the enemy heroes’ level) and –afk (to make sure that the player is indeed playing and not idle). If the “missing” enemy hero is not afk and is gaining levels, then scouring the woods by yourself or with a teammate every so often is a good idea to disturb and kill a jungling hero.

Good Old Ambush. The traditional, most straight-up way to gank a hero is simply considered a heat of the moment opportunity, where one takes advantage of a given situation. Many times, heroes will venture too far out of their safe zones when they are unopposed by an enemy for some time. Moving through the forest to ambush the hero is standard for DotA games.

How to Avoid Ganks

The concept of avoiding ganks is easier said than done.

To ultimately avoid being a victim of ganks, the most important thing to keep in mind is map awareness. Checking the minimap every so often makes you more alert regarding enemy whereabouts. Early game, heroes tend to stay on one lane most of the time.

If one enemy hero leaves his lane, there are a couple of things that he could have done: He can either have gone back to the fountain to heal and buy some items, check runes, or ultimately, orchestrate a gank.

As part of a team, it’s somewhat your duty to call missing heroes. This means you should tell your allies that your lane’s enemy heroes are missing in action. You can do this by simply typing “missing (your lane)” or any variable of that such as “mis bottom” or “mia top”. This would greatly help your allies be more aware of their surroundings as well.

Another way to avoid ganks is investing in the purchase of Observer Wards. These items give you a line of sight on areas where heroes might attempt a gank (such as forest entry and exitways) so you can move away when you see incoming enemy heroes.