For example a tire size of 205/55R16 indicates it has a section width of 205mm (nominal), 55 an aspect ratio of 55% (ratio of tire sidewall height to section width H/S) and 16 the rim diameter in inches the tire can be fitted.
Following the tire size information is the service description e.g. 91V indicates a load index of 91, by referring to the load index table shows a maximum carrying capacity of the tire of 615kgs and V a maximum speed of 240km/h (150mph).
The tire age can also be found by examining the characters following the symbol "DOT". The last four numbers identify the date of manufacture of the tire to the nearest week. The first two of these four numbers identify the week of manufacture (which range from "01" to "53"). The last two numbers identify the year of manufacture (e.g., a tire with the information "DOT XXXX XXX 3112” was manufactured in the 31th week of 2012).