The built-in digital receptionist (IVR) explained

Your Free SIP Account includes a digital receptionist, also known as an auto-attendant or IVR (Interactive Voice Response). This is the automated menu that greets callers — "Press 1 for sales, press 2 for support" — and routes them to the right extension, ring group or queue.

You build the menu in your account and attach a recorded greeting to it (see our optional recordings and custom-audio features). An IVR lets a one-person business sound like a full department, and lets a small team make sure calls always reach someone who can help. Combine it with time conditions so that out-of-hours callers hear a different menu or go straight to voicemail.