What is communication software?

*OfficeIntercom Communication Software

OfficeIntercom lets you use your computer to speak to others over the internet or your local office computer network. It works as a virtual intercom and feels a little like using a CB radio. To talk to anyone else who has installed OfficeIntercom anywhere in the world, just hold down a key on the keyboard. Speak into your computer's microphone and you will be heard through the other computer's speakers. You can assign system-wide 'hot' keys, or use hardwired buttons or a SpeechMike handset to connect directly without opening OfficeIntercom.

Here I just give only one example. You can search the website by yourself.

http://www.globalshareware.com/internet/Communications/

I hope it can help you.