Yelp Inc. was founded in 2004 by former PayPal employees to provide reviews of local businesses online. While the company has grown significantly and gone public, it remains unprofitable due to high sales and marketing expenses required to expand into new markets. The company currently generates most of its revenue from advertising but faces challenges in maintaining business clients and keeping users engaged with the platform. To improve its financial situation, Yelp may need to focus on enhancing the user experience, developing new revenue streams, and controlling marketing costs.