Asterisk
Asterisk is an open-source framework for building communications applications, primarily used as a Private Branch Exchange (PBX) system for voice over IP (VoIP) telephony. It enables developers to create and manage features like call routing, voicemail, conferencing, and interactive voice response (IVR) systems. It supports various telephony protocols, including SIP, IAX, and H.323, making it a versatile tool for voice and video communication solutions.
Developers should learn Asterisk when building or customizing telephony systems, such as business phone systems, call centers, or unified communications platforms, as it provides a flexible, programmable foundation. It is particularly useful for scenarios requiring integration with web applications, CRM systems, or custom IVR flows, offering cost savings and control compared to proprietary solutions. Use cases include VoIP deployments, telemarketing automation, and emergency notification systems.