VoIP is Voice over Internet Protocol which allows to voice chat. Some of the VoIP services are Whatsapp, Messanger, Viber, Telegram, Discord, etc. What is your favorite VoIP service? Well, I use VoIP to communicate with my friends and family through Messenger. As far as communicating with clients, I do not use VoIP too frequently, however, if I have to use I will be using Telegram or Discord.