Difference Between Orientation Sensor and Accelerometer Sensor

I want to know about the values of X,Y and Z axis for any position/movement of device so I can use these values for my further work. As I searched there are two methods, Orientation Sensor(gives value in degree,as azimuth,pitch and roll) and Accelerometer(gives values between 1 to 10 for x,y and z).

As per my understanding both are same for my requirement. I can't find difference between t开发者_如何学Gohem. Please can any one clear me about them in detail w.r.t my aim. which sensor should I use?

There are differences between both:

Accelerometer detects acceleration in space. The reason why it will always detect an acceleration of 9.8m/s^2 downwards is because gravity is equivalent to acceleration in space.

Orientation detects if your device's axis are rotated from the real-world; it detects tilts and and degrees from the magnetic North. Please note that this sensor is deprecated and Google recommends you use the accelerometer and magnetometer to calculate orientation.

You'll need the accelerometer to detect movement. So you should use this one, since your aim is to know this movement.

The orientation sensor gives information about its position compared to a reference plane. So you could use this to see of the device is tilted, upside down or something like that.