I have to specify what year I am talking about because Sony is so bad at protecting itself from hackers. This most recent hack is still up in the air if North Korea was involved but there is no actual proof out there that would suggest so or even suggest otherwise. So far the only people taking responsibility for hacking into Sony is a group of Guardians of Peace. They are a group of hacktivists, the reasoning behind the attack is they believe Sony is greedy and use criminal business practices. Another reason for the hack, was the movie, The Interview, once the hack became known, Sony decided it wouldn’t release the movie. President Obama ended up telling Sony that they were making a mistake and Sony decided to change its decision and released the movie online, in theaters, video-on-demand, and a few others.
The hack was so damaging and massive that Sony has set aside $15 million to investigate the hack and to try to fix things. The hack was so bad that they had to shut down some of their systems for it to not create anymore damage to any other systems. When they first shed light on the hack, it was to believed that the hackers got as much as 100 terabytes of data from Sony.