SoftPhones are really just software that runs on your computer and emulates a real telephone. They usually render an image of a telephone or a windows interface that provides the user with buttons for dialling, disconnecting, volume controls, etc.
The softPhone often has many optional features such as phone book (contact list), redial, call record, conferencing, call history, and perhaps many other optional features.
The future trend is for softphones to be web browser based, in which case there is no software to down load.
Generally speaking, there are two categories of softphones:
A good example of a user-configurable softphone is the 3CXPhone softphone. In a later topic, I explain how to configure the 3CXPhone softphone with one of my favourite VoIP service providers - Voipfone.