Voice over IP (VoIP) moves voice and video over the internet. Basic requirements are an internet device, microphone/headset, and a VoIP client. Free apps handle peer-to-peer calls, while paid VoIP carriers bridge calls to regular phone networks and offer business features like SIP trunking. Call quality depends on your network, and emergency calling behaves differently with VoIP - providers usually require a registered location.
What VoIP is and why it matters
VoIP stands for Voice over IP - transmitting voice (and often video) over the internet instead of the traditional phone network. Since the 2000s the technology has matured. Today you can place calls from a smartphone, laptop, or browser and often pay less than with legacy long-distance services.What you need to make VoIP calls
Most basic VoIP calls require:- An internet-connected device (computer, smartphone, tablet)
- A microphone and speakers (or a headset)
- A VoIP app or client (examples below)
- Sufficient broadband bandwidth
Free vs. paid VoIP options
Many services now offer free voice and video between users of the same app - examples include WhatsApp, FaceTime, Signal, and Microsoft Teams (for internal users). Other services (Skype, Google Voice, Zoom) mix free peer-to-peer calling with paid options for calling landlines and mobile numbers.Paid VoIP plans often include local phone numbers, outbound calling credits, business features (auto attendant, call routing, analytics) and PSTN termination. These features make VoIP attractive for both individuals who call internationally and businesses that want to reduce telecom costs.
How VoIP fits into modern communications
WebRTC and browser-based calling let people place voice and video calls without installing native apps. Unified Communications platforms (e.g., Microsoft Teams, Zoom) combine voice, video, messaging, and collaboration in one service.VoIP supports significant cost savings for international and long-distance calling, but results depend on network quality and the provider's PSTN interconnect rates.
Practical considerations and limits
- Call quality depends on bandwidth, latency, and network congestion. Use wired or robust Wi-Fi where possible.
- Emergency calling: traditional 911/E911 behavior differs from VoIP; many providers require users to register their location for emergency services and have specific regulations governing emergency calls.
- Interoperability: some features (fax, alarms, proprietary codecs) may need special configuration.