A hacker is one who enjoys the intellectual challenge of creatively overcoming and circumventing limitations of programming systems and who tries to extend their capabilities. The act of engaging in activities (such as programming or other media) in a spirit of playfulness and exploration is termed hacking.
However the defining characteristic of a hacker is not the activities performed themselves (e.g. programming), but the manner in which it is done: Hacking entails some form of excellence, for example exploring the limits of what is possible, thereby doing something exciting and meaningful.
Hackers from this subculture tend to emphatically differentiate themselves from what they pejoratively call "crackers"; those who are generally referred to by media and members of the general public using the term "hacker", and whose primary focus—​be it to malign or malevolent purposes—​lies in exploiting weaknesses in computer security.