An SMS gateway is a technology that allows you to send and receive SMS messages through a secure web interface, without needing to have your mobile phone physically with you. You can use your personal phone number or choose to buy a dedicated SIM card for your private messages. This SIM card can be placed in a device that does not need to be accessible or visible; it can be safely hidden or stored away. As long as the device has an active SMS plan and an internet connection (3G, 4G, 5G, or Wi-Fi), messages are sent and received through the web interface in a completely private and secure manner.