Answer :
4 common tangents = circles do not touch
3 common tangents = circles touch at one point
2 common tangents = circles overlap
1 common tangent = circles touch at one point and one is inside the other
0 common tangents = circles do not touch and one is inside the other
Refer to the image if you need to
3 common tangents = circles touch at one point
2 common tangents = circles overlap
1 common tangent = circles touch at one point and one is inside the other
0 common tangents = circles do not touch and one is inside the other
Refer to the image if you need to
![View image RedRicin](https://us-static.z-dn.net/files/db3/d5bbc6108b4ec3f5436d44f48e312e88.png)