There are many times when a vehicle's battery has given up and we have to put it in front either to charge it, or to drive the vehicle to the electrician or workshop. Battery discharge can be caused by prolonged immobility, damage to the battery and charging system, or a number of other factors.

Of course, the ideal case would be to be able to avoid the whole process, simply with a phone call to a battery delivery service. In a very short time, a qualified technician will come to the place where the car is, change the battery with a new one of the exact type and specifications we need, without any intervention of ours. Before leaving he will also do a check of the dynamo's electrical charging system and take the old battery to be properly recycled.

The next best case scenario is to use a vehicle starter. All we have to do is open the hood, connect the starter wires to the two battery terminals and simply turn the key in the ignition! With a launcher we don't need anything at all and the process is over in seconds!

But usually there is no starter and cables and the help of another car's battery are used. It would be good before we start anything to take into account the positions of the batteries and their poles in the two cars, as well as the length of the cables, so that we know from the beginning how to connect them.

Before connecting the 2 batteries in parallel, make sure that all the car's systems (eg lights, radio, etc.) are off.
We also make sure to connect the positive pole of one battery to the positive pole of the other and the negative pole of one back to the negative pole of the other. It is no coincidence that the starter wires have different colors (red and black respectively). In the event of a wrong connection, a spark will be created with an immediate risk of fire, while the (sensitive) electronics of the car are also at risk.
After putting the engine in front, we disconnect the cables very carefully, starting first with the negative (black) from both cars and moving on to the cable connecting the positive poles (red) of the two batteries. Something like this protects us, so that in no case do the terminals from the positive and negative poles of the same battery come into contact.
Finally, just in case, it would be good to have the car's first trip check the battery and the electrical system by a qualified electrician.