A guy's short description of rebooting
In a nutshell; the idea is to give up an addiction, whether that be pornography, masturbation, or both (and usually they go hand in hand). The goal isn't to become sexless monks, but rather to enhance your sex life by going through a brain "reboot." Since pornography, our brains have become so accustomed to the visual side of fake, onscreen sex that we no longer react simply to a woman's kiss or a light touch. We begin to make excuses not to go out and meet people or get girls because we've become perfectly happy living in our fantasy world, where you can simply pleasure yourself and not have to worry about finding someone else to do it for you.
Conditioning the brain this way is unhealthy, and it has led to a lot of problems in the bedroom for many many men and women. The "reboot process" is done through giving up PMO (porn, masturbation, orgasm) for at least 90 days, letting your brain revert back. Your brain will heal, giving up the desensitizing harm that porn has done to it and be able to view sex in a better, more intimate light.
During this process, some people still choose to have orgasms as long as they are from real intercourse (though its said that it slows down the process for some people). Personally, I plan on going without porn or masturbation. I will have sex, but I plan on going without it for at least the first 30 days.
All in all, you're ridding yourself of an addiction; whatever you think that means to you. You're allowing your brain and body to stop being dependent on it. Its probably not for everyone, but I've read through all the benefits that seem to come from it and have decided I want that for myself, so I'm giving it a shot :)