VoIP (Voice over Internet Protocol) is a digital telecommunications technology that lets users make/receive voice calls over the Internet instead of the standard landline telephone network (the PSTN.)
It works on devices with Internet access, meaning analog phones, (desk phones or hard phones connected to the VoIP system) smartphones, tablets, desktop computers, and laptops can all be used for VoIP calling.
In addition to greater mobility, VoIP offers more advanced features, a higher level of customization, and significant cost savings compared to traditional phone lines. it also referred to as IP telephony, virtual telephony, or Voice over IP calling.