1. The Original Logic Bomb:

The original logic Bomb is considered to be the one of the best and most expensive of all the cyber attacks. During the cold war in 1982, CIA found a way to disturb the operation of a Siberian gas pipeline of Russia without using traditional explosive devices such as bombs. Instead, they crashed the Siberian gas pipeline to explode. They used the portion of code in a computer and controlled the operation in the computer, and that was termed as the “logic bomb”. It is considered as the best cyber attack of the world.

2. Epsilon:

Epsilon is considered to be one of the costliest computerized attacks in the world. All above mentioned electronic attacks are cheaper than Epsilon. It provides best services in the market such as Morgan Chase, best buy and other major financial services, retailers and other major companies in 2011. The damage was estimated to be of $225 million and $4billion. The targets of the hackers were email accounts that they can use with their criminal activities. It is the world's best and most expensive cyber attacks.

3. Sony:

In 2011, 77 million of play station network and Sony online entertainment accounts. Including credit and debit card information and the information was hacked by the unknown group of computer hackers. The damage was estimated to be of $1 to $2 million dollars. It is also one the famous and the most expensive company of cyber attacks. Microsoft spent much of the money on the development of the company.

4. Michael calce:

Michael Calce is from West Island. He was an ordinary boy of fifteen-year-old and famous as Mafiaboy. It is the very famous hacking company from 2000 with high-level security. It includes computer giant Dell, Yahoo, Fifa.com, Amazon, Ebay and CNN, and the damaged was caused $1.2 million. It is considered to be the eighth most expensive country in the world.

5. Sven Jaschan:

Sven Jaschan is considered to be the ninth most expensive computerized attack. Sven Jaschan is a German college, student. He unleashed the virus on his eighteenth birthday in 2004 that showed its results all over the world. The damage was estimated to be of $500. Microsoft has put $250000 by this attack. It is the most famous and expensive electronic attack and a huge amount of expensive were made on it.

6. TJX:

The owners of the company are TJ Maxx and Marshall. They can manage 45 million of debit cards and credit cards information. The data breach has resulted in $250 million in damage as Gonzales on ten of hi crews seek their reward. It is considered to be the tenth most expensive cyber attack. Microsoft put the expense of $250000 of on this cyber attack.

7. Citigroup

Tremendous amounts of wealth, from thousands of parties, flow through financial giants such as Citigroup on a daily basis. Earlier this year, in 2011, the aforementioned stacks of money and hoards of sensitive customer information provided ample incentive for cyber-hacks to organize an attack. Over 200,000 customers' names, contact details, account numbers and other information were compromised in the attack, as the thieves made off with $2.7m from credit card accounts. That's a bad day at the office.