DNS: Internet’s Directory Nearly everything on the Internet starts with a DNS request. DNS is the Internet’s directory. Click on a link, open an app, send an email and the first thing your device does is ask the directory: Where can I find this? Unfortunately, by default, DNS is usually slow and insecure. Your ISP, and anyone else listening in on the Internet, can see every site you visit and every app you use — even if their content is encrypted.