DoubleClick Ad Exchange is a real-time marketplace to buy and sell display advertising space.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.