This is software that stimulates the action of a telephone and allows you to make, receive and manage voice calls over the Internet (http://voip.about.com/od/ glossary/g/SoftphoneDef.htm). This software is very common and is usually already installed on computers, tablets and smartphones. They contain an interface that acts as a communication platform between users and the device. There is also a call processing engine. This allows you to make and receive calls. Codecs allow voice data to be encoded between analog. This makes it easier to transfer over the Internet. Finally, there is a contact list that helps keep track of numbers and