Emergency situations can come up when you least expect them, that's why it is important to be prepared! Icy, snowy or wet roads could put your car into an embankment. Mechanical car issues, like overheating, dead battery, or even out of gas can leave you by the roadside or in a parking lot. It's important to note, things happen. That's why keeping some emergency supplies in your car is a good idea when those things happen.
Here are 10 items to consider.
1. Toilet Paper and Paper towels. You never know when you might need paper, and not only for the obvious reason we have toilet paper. Toilet paper can have many uses, such as writing paper, keeping track of the hours or days you may be stranded by marking or removing the single sheets and placing them in a pile. If you are injured, and can access, it may help as gauze or a loose bandage. If the weather is hot, it could be used to wipe perspirations. Outside the car, you could use it as a "bread crumb trail" when exploring the area around your car. It could be used as kindling to start an emergency fire. These are just a few ways one might benefit from having toilet paper and paper towels.
2. First Aid Kit. Every car should have one of these. First Aid Kits can be purchased pre-made or you can make your own. Common items found are limited amounts band-aids, 
antiseptic, healing ointment, and some sort of pain killer, such as Tylenol or Ibuprofen. Other items to consider adding: Benadryl, plastic or latex gloves, gauze, medical tape, medical wrap (to wrap an ankle, wrist, head, or leg), a serving or two of your daily medication/vitamins and anti-nausea medicine.
3. Fire Extinguisher. Truckers usually have one in their cab. Not only is it helpful to extinguish fires, but it could also be helpful if there was a car accident and a window needed to be broken to help someone out. Or if someone were trying to attack you, you could turn the fire extinguisher on them to help you elude capture.
4. Jack and Lug Wrench. Learn how to change your own tire safely.
5. Blanket. Having a blanket available when you are cold, stressed, injured, or all of the above, is comforting. A blanket can also be used to cover the ground to have that impromptu picnic (assuming you have some food available). It can be used to help others warm up, if they have fallen into water. It can be a temporary roof over your head, protecting you from the wind. You can use it to sleep on or underneath.
6. Jumper Cables. These should also come standard with every car and learn how to use them properly. (It is not difficult!) These can be used on your car or anyone else's vehicles who are suffering from a dead or low battery.
7. Extra Gloves. In the winter, throw an extra pair of gloves in the car. You never know if your set will get wet and you need another pair. Or you may see someone who could benefit from a warm pair or even one glove.
8. Water. No matter the season, it is good to keep a couple of bottles of water in your car. In the summer or when the temperatures in your car cause excessive heat to build up in the car, store water in glass or stainless steel water containers. Otherwise, most plastic bottles are fine.
9. Food. Keep a couple of shelf-stable edible bars, cookies, or candies in your car. Being stranded or waiting on someone to come rescue you is not fun, particularly when you have no idea how long it will take. Having a small snack available while you wait a couple of hours or a couple of days, is worth taking the time to prepare.
10. Extra Shoes. Keep an extra pair of shoes in your car, when the pair you have is either uncomfortable, gets damaged, or to donate to someone in need.
There could be many other combinations, depending on your need -- such as extra make-up, a bucket, phone charger, a plastic container, an air compressor, freezer bags, pens, tweezers, dog leash, dog bowl, trash bags, maps, and even a toy or stuffed animal.
Watch Out For Others
We can't foresee the future, and we must be prepared for ourselves and for our fellow Americans as we travel.