How does the observer work?

How does the observer work? The Observer will detect the state of the block it is observing, along with placed or broken blocks. Once a block state change is detected, the Observe will send out a Redstone signal from the back. (opposite of the face) An example of this could be if an Observer observes a crop growing.

The Observer will detect the state of the block it is observing, along with placed or broken blocks. Once a block state change is detected, the Observe will send out a Redstone signal from the back. (opposite of the face) An example of this could be if an Observer observes a crop growing.