Cracking is invalid means by which one not only gets the Control of other's Computer and gains access on the Information stored in it but also modifies it or misuses it or destroys it.
Cracking is the advanced process of Hacking.
In Cracking the Information is destroyed to avoid its Use.
Also, sometimes the information is modified to misguide.
Cracking involves a difficult process of Calculations to break or identify the code.