The module contains an integrated circuit with MPU-6050 accelerometer, gyroscope and temperature sensor. It communicates the I2C interface, needing only 2 connections. Each device that uses I2C interface has its own address. MPU6050 can select one of two available addresses, connecting to GND or VCC pin AD0. This connection is usually made on the module board. It is useful in your projects that need to detect movement and its intensity, such as gaming, image stabilization, step counter.