The goal of this research is to explain one of the most interesting technologies that exist today, Internet of Ships (IoS), the IoT applied to the maritime sector. This technology is an enabling of other existing within what is known as Industry 4.0, such as the digital twin, cloud calculations or augmented reality.
 Something as common as barcodes, were precursors of this technology and have been the cause of many stores have made the leap to smart tags, like RFID ones, which help them to perform both inventory and collection of things in the cashier, making that one jacket in the store an individual item in the collection of objects but perfectly controlled by the system. During the last years we have worked on implementing this transversal technology in the naval industry, and in this paper some examples will be shown.