Head torches are compact torches which can be worn on the head with an elastic band. In this way, you always keep your hands free to do whatever needs to be done.
In general, the torches are powered by one or more AA batteries. Sometimes, the head torch has a battery compartment that can be carried separately. This is nice, because then the weight of the batteries is not always on your head. An extra advantage is dat the you have the option of carrying the batteries under your clothes. With low temperatures, that makes a huge difference for the burn time.
If you rarely need a head torch, there is an alternative: a head band in which you can mount a 'regular' compact torch. This has to be a compact model, to limit the weight. It's also possible to attach a torch to a helmet, for example at construction sites. Click here for these accessories.