Video door-phone

A video door-phone is a gadget that allows you to see and talk to the person who is at your front door without opening it. When someone comes to your house and rings the doorbell, instead of just hearing their voice through a speaker like a walkie-talkie, you can see their face on a small screen. This is so that you can decide if you want to let them in or not, and you can even ask them questions or give them instructions.

It works like this: A video door-phone has two main parts: an outdoor unit, which is mounted near your front door, and an indoor unit, which is usually installed near your regular phone or on a wall in your house. The outdoor unit has a camera, a microphone, a speaker, and a button for visitors to push when they arrive. When someone presses the button, the camera in the outdoor unit sends the video signal and audio signal to the indoor unit in your house using a cable or wireless connection. Then, you can see the visitor's face on the screen of the indoor unit, and talk to them using the microphone and speaker on the indoor unit.

Some video door-phones even have extra features, like recording videos of visitors or taking photos, so you can keep a record of who came to your house even when you weren't home. There are also video door-phones that can connect to your smartphone or tablet, so you can see and talk to visitors even when you're not at home.

Overall, a video door-phone is a handy device that helps you stay safe and secure, while giving you a convenient and easy way to communicate with visitors.