The author, Jarod Reyes, explains how to add SMS functionality to a web app using the Twilio Platform, which requires only four lines of code. He provides examples in PHP, Ruby, Node.js, Python, C#, and Java. The article discusses how Twilio works, including sending outbound messages and receiving inbound messages with TwiML instructions. The author also covers basic setup, installing helper libraries, and using the REST API to send and receive SMS messages. Additionally, he mentions various use cases for SMS capabilities, such as two-factor authentication, notifications, proactive alerts, mobile app distribution, and more.