How does craigslist.org work? It’s simple - people who need manpower need to do advertising on craigs list. Mostly placing an advertisement is free on craigslist.org. Craigslist is among the most visited website in the world, with over 5 billion page views per month. The site serve over over 10 million new classified ads each month. Craigslist.org is not only a leader in classifieds, they are also among the top job job sites in the world.