SPPID_How to move one component to another one

Sometimes, we need move one component connect to another one; in another word, reduce the line between these two component into "zero".
The correct way is:
1. make sure everything is on grid.
2. click one component, then click move.
3. when the arrow point is close to another component, the line will shows red, then you can see clearly the connect point. just release your left mouse key, it will automatically connect to the point.
4. check the property, the "connector zero length" will show "True".