Craigslist is a local community website that allows residents to post information about real estate, jobs, tickets, and events. It has sites in 300 cities across the US and abroad, with 10 million unique users per month. Though Craigslist continues to grow in revenue, most advertising is free, which has taken a toll on advertising revenue for other media like newspapers. However, Craigslist's free classified posts have drawn some criticism for potentially eliminating local newspapers and allowing problematic ads like those selling pit bulls.