Call came in, rang twice; I answered with hello and they hung up. They don't need to waste both of our times. If it is a home improvement as suggested in above anecdote, perhaps they recognized my voice. I have explained to such folks that I have my own people for home improvement.
I got a call from this number. The guy was asking for my mom and he was very aggressive and threatening. When I asked the male caller who this was he said something like "Chupa." I asked what it was regarding and he was like "she knows why I am calling and it's not about the garden." My mother knows such person.
It's a device which you hook up to your land line phone which will block unwanted calls. Digitone Communications sells one for $100. It's well worth the price. However, it won't work with cell phones or wireless phones. It will work with land line phones connected to an external wall jack. It will also work with "Magic Jack" which is a Voice Over Internet Protocol" (VOIP). Good luck.