1º_ A series of links, usually metal, joined together to form a strip that is used for fastening, since it has the flexibility of a rope and the strength of the material with which it has been built. There are also drag chains, such as on bucket dredgers or on the tracks of off-road vehicles. If it is made of a noble metal, it can also be decorative, such as jewelry. See link . 2º_ By the above, any sequence, facts or objects that are found one after the other. 3º_ By association with the "union of similar and individual elements" the group of companies, branches or related establishments is also called 'chain'. 4º_ Related to the chains to prevent the escape of the inmates, it is also a way of calling a penalty, a condemnation. Although it is an obsolete term today, we still find it in the expression "life sentence".