There are good and bad definitions for hacking. You can use hack for the good as said by these websites:

Learning to hack, so you can make games

The ethics  in hacking

Hacking Ikea to make cool stuff

But there are also ways to use hacking for the bad, as said by these websites:

Hacking netflix to get free movies

Hacking PSN, causing disruption. 

Hacking to attack a group of people


Hacking: To adapt with a pursuit to solve problems, and overcome limits