This document describes a home surveillance system that uses a Raspberry Pi connected to an ultrasonic sensor to detect intruders. The system is designed to monitor a home or shop for security purposes. When the ultrasonic sensor detects an intruder based on distance readings, it sends an alert message and photo to the owner. The system aims to automatically detect intruders, unlike CCTV which requires constant video review. It uses low-cost hardware and provides real-time alerts to help prevent crime.