I always carry a pair of jumper cables in my car. I have found this to be a good insurance policy. Over the years, I have used them but a few times. However, each time they had been a tremendous blessing either to me or to someone else. Every car should be equipped with one. They are like the spare tyre; you never know when you are going to need them, but need them you will. Although the car battery can theoretically work forever, in practice I find that on average I have to replace the battery every five years or so.
Jumper cables don't cost much, and they don't take up much room in the car. If you don't have them, get them now and make sure you know how to jump start a car. When your battery goes flat (which it inadvertently will at the most inconvenient time and place) you'll be thankful you read this blog.