Many industrial companies are now getting on board the new industrial revolution dominated by data acquisition, digitalization and other new technologies. Wearables combine the features of some of the most popular technologies of this revolution: they can monitor specific body regions by tracking information anywhere and anytime. Wearable systems for hands represent a special field of interest since they are the main body region involved in industrial tasks. This paper surveys such wearable systems based on the data from the last years. It collects information about the most important components they incorporate and analyses their features considering that they are devices aimed to be worn on the body. Thus, this paper is addressed to researchers who want to understand what a wearable is and which the main components and characteristics should incorporate, and also, those who want to explore new trends in this research field.