Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PayPal is an online payments system that supports online money transfers and serves as an electronic alternative to traditional paper methods like checks and money orders.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.