Twilio Radio is a podcast that features interviews from speakers presenting at SIGNAL, Twilio's developer conference for communications. The podcast covers topics such as text messages and SMS, including why SMS is an effective communication medium for businesses, technical differences between SMS and MMS, and best practices for scaling a Twilio messaging app. Additionally, the podcast discusses developer culture and project management, with insights from Karen Cohen-Zellner on building strong developer culture and autonomy within teams at large companies like Wix. The podcast also addresses topics such as job searching and negotiation, providing practical advice for developers looking to start or change their careers.