It's not really a good idea to jump start a car with jumper cables from another car battery:

The last connection made will make a spark; batteries can produce flammable gases, so this presents a fire risk.

It's easy to get polarity mixed up, especially on a dark night.

If the car with the dead battery has problems in the electrical system, it can damage the electrical system in the car giving the jump.

As a practical matter, it can be difficult to get the two cars positioned so the jumper cables can reach. This is especially true on busy highways.

Some good products are available to help.

StartMeUp2 is a one time use, disposable jump starter that's small enough to fit in your car's glove compartment. You don't even have to get out of your car to use it; you just plug it into your cigar lighter, and in about 5 minutes, you should be able to start your car. This product has been featured on the Oprah show and is great for women. About $20.

Compact battery jump starters like the Coleman Powermate PMJ8960 weigh about 10 pounds and can be kept in the trunk. They are easy to get close to the dead battery and don't run the risk of zapping another car's electronic circuits. These can be used over and over. about $45.

These give a lot of peace of mind and make a really great gift for anyone.