The first two columns are the major and minor numbers respectively. The third column is the number of blocks (usually 1 block = 1024 bytes). The fourth column is a label for the device.
Les dues primeres columnes contenen el número major i menor respectivament, la tercera, conté el nombre de blocs (usualment 1 bloc = 1024 octets). La quarta, conté una etiqueta per al dispositiu.