Still not 20 years, but it's probably better to start at Office Communicator which was from 2007. Skype for Business was a rebrand of a rebrand of that, and apa

Still not 20 years, but it's probably better to start at Office Communicator which was from 2007. Skype for Business was a rebrand of a rebrand of that, and apart from name has no relation to Skype.