Here is a picture of an electric service drop in disrepair. An electric serivce drop connects electric power from the pole to the electric meter before entering the house. Oftentimes, it is mounted right on the side of the house. This one is mounted on a pole in the backyard.
As you can see, the insulation is compromised and not effectively keeping out the elements. What is revealed inside is the braided ground wire which surrounds the two hot black 120 volt conductors. If the insulation on your electric service drop looks like this, it's time to call a qualified electrician.
If you have questionable wiring in your house, send us a picture at: firstname.lastname@example.org. We'd love to hear from you!