Asterisk is the world's leading open source telephone and communications system.

Asterisk is a free and open source framework for building communications applications and is sponsored by Digium .

The asterisk website provides full information about the Asterisk PBX.

We have presented some brief excerpts from the site to give you an inrotudction.

It comes with a rich integration with traditional and modern communication protocols and telephony hardware compatibility.

Asterisk is in use today as the core engine of many communications applications. While business phone systems (also known as IP PBXs) are the most common, Asterisk includes components that allow it to serve a wide range of functions.  This section of the Asterisk.org site is intended to help you understand how Asterisk influences some of the most common applications. Keep in mind that these are only a small sample of the thousands of things that have been built using Asterisk.

With Asterisk, you have the potential to tie communications into any application or business function. The ultimate goal of Unified Communications is to build multi-modal communications capabilities into the applications you use.  Asterisk makes this easy.  Communications-enable your salesforce automation or CRM system using the Asterisk Manager Interface.  Set your workforce free by adding mobility and remote worker capabilities.  Up your customer service efficiency and delight your customers by implementing web-based callback and intelligent queuing.

Asterisk-based telephony solutions offer a rich and flexible feature set. Asterisk offers both classical PBX functionality and advanced features, and interoperates with traditional standards-based telephony systems and Voice over IP systems. Asterisk offers the advanced features that are often associated with large, high end (and high cost) proprietary PBXs.