It's common practice nowadays to pooh-pooh punishment in favour of never-ending positivity, which for most people brings to mind rewards and encouragement. The truth is that rewards can also be highly damaging, destroying motivation and create the very opposite behaviour that parent's are trying to nurture. It isn't nearly as simple as chosing one over the other. Below I give the rules-of-thumb to use rewards effectively.
Conditioning, using rewards and punishment, is a very basic form of psychological behaviour modification that you can use to teach (or program if you will) worms, dogs, and humans. The prerequisite is a nervous system, and maybe not even that. The good thing about that is that it works even with small babies!
When I wrote the punishment article, some people thought that I meant beatings or groundings. I simply meant anything that the child dislikes. Similarly, rewards are anything the child likes or wants more of. Candy, money, watching a movie, toys, a kind word, an exciting outing, are all examples of rewards.