How do pheromones work in humans?

So what's this i hear about the inbuilt pheromone radar system we have that checks out likely mates for their suitability? I know that everyone has their own unique scent, and that people that share certain characteristics have similar scents, and that there are those who's pheromones we simply "like" or "dislike"... I've also heard that birth control pills can cut off the receptability of this sense. I just find this whole thing very interesting and would like to know more about it. How does it work exactly? How does it vary from person to person? How can you become more aware of and in-tune to this sort of sense (if it exists? ) i would at least like to be directed to resources where i could learn more about it if there isn't much you know about it. Thank you.