The top wires are electric. Those are the ones that are thin and are usually the ones held up by a crossarm and secured in insulators. There can be one, two, or three of these such wires.
The wire with another wire or so spiraled around it is also electric. Usually, there is only one of these, but can also be none in some cases. Sometimes this wire doesn't even have another one spiraling around it.
This kind of wiring has been gradually replacing the (usually) three wires that are below the top wires.
The electric wires were formerly thinner in diameter, and have been made slightly thicker for some time now.
The bottom wires are telephone. These are usually much thicker in diameter. The number of these can vary similar to how the thin electric wires vary.
Over the years, they have been replacing the much thinner wires that also used to be on the bottom, of which sometimes there were several of these thin wires. Most of these surviving thinner phone wires can be found in less populated areas, and can sometimes even be thinner than some electric wires.
The next-to-bottom are cable TV wires. They are similar looking to the telephone wires, except that they are usually gray in color, but sometimes can be black. Also, the thicker part of the cable wire dips down just about where the pole is located. This dipped-down part is where a cable wire that goes to a house is attached.
More recently, some cable wires began having a teardrop shaped piece on them. Perhaps it has something to do with upgrading.
In recent years the cable companies have found it easier to carry their television (and now often telephone and internet) signals over longer distances by installing fiber optic cables, which eventually connect to coaxial cables for local neighborhoods. These fiber cables are bundled together with the standard coaxial cables, using the same messenger wire for support. Whenever a splice must be made, excess cable is needed to allow the splicing (for fiber optics this is a delicate operation involving expensive equipment) to be done on the ground, often in an enclosed trailer dedicated to this task. Once the splice is done, the excess cable is usually strung back and forth along the messenger cable and tied to it for some distance. Where the cable changes direction to go back and forth like this, they use a teardrop shaped device which protects the cable where it loops. Fiber cable cannot be bent very sharply without being damaged, so they need a rather large loop in it. This device prevents the loop from being pulled too sharply.ethan
This process is also repeated at somewhat regular intervals along the cable, even where there is no splice. This is so that, if there is ever a cable cut, and the cable must be spliced, extra cable will be available for this purpose. All that is necessary is to loosen the lashing wire and slide the cable from the nearest loop point down to the splice. Otherwise, they would need to make two splices due to lack of cable, which would add expense and hurt line performance.]
There are one or (usually) two very thin wires right above the telephone wires. I eventually found out that they are firemen's wires. Especially on older poles, they are held up by short crossarms. These wires are most likely connected to the red and white fire boxes for reporting fires.