Hacking is really just the act of finding a clever and counterintuitive solution to a problem.
The hacks found in program exploits usually use the rules of the computer to bypass security in ways never intended. Programming hacks are similar in that they also use the rules of the computer in new and inventive ways, but the final goal is efficiency or smaller source code, not necessarily a security compromise. There are actually an infinite number of programs that can be written to accomplish any given task, but most of these solutions are unnecessarily large, complex, and sloppy. The few solutions that remain are small, efficient, and neat. Programs that have these qualities are said to have elegance, and the clever and inventive solutions that tend to lead to this efficiency are called hacks. Hackers on both sides of programming appreciate both the beauty of elegant code and the ingenuity of clever hacks.
In the business world, more importance is placed on churning out functional code than on achieving clever hacks and elegance. Because of the tremendous exponential growth of computational power and memory, spending an extra five hours to create a slightly faster and more memory-efficient piece of code just doesn’t make business sense when dealing with modern computers that have gigahertz of processing cycles and gigabytes of memory. While time and memory optimizations go without notice by all but the most sophisticated of users, a new feature is marketable. When the bottom line is money, spending time on clever hacks for optimization just doesn’t make sense.
True appreciation of programming elegance is left for the hackers: computer hobbyists whose end goal isn’t to make a profit but to squeeze every possible bit of functionality out of their old Commodore 64s, exploit writers who need to write tiny and amazing pieces of code to slip through narrow security cracks, and anyone else who appreciates the pursuit and the challenge of finding the best possible solution. These are the people who get excited about programming and really appreciate the beauty of an elegant piece of code or the ingenuity of a clever hack.
-- Hacking : the art of exploitation / Jon Erickson. -- 2nd ed.