How does nicotine gum work?

Right now I'm using nicotine gum to stop smoking. I find it strange because I don't get the same effect from the gum as from smoking previously. However, it has been a month since I stopped and I have very few cravings. I'm a very skeptical person and I'm wondering what your thoughts are on nicotine gum? Is it partially a placebo effect? I'm not complaining at all because It's great to not be smoking. I just find it strange that I don't get the old "buzz" like i did from the nicotine in smoke, yet the gum helps curve the cravings.