Celebrations generally involve public parades and festivals, céilithe (Irish traditional music sessions), and the wearing of shamrocks, as well as green or orange attire. There are also formal gatherings such as banquets and dances, although these were more common in the past. St Patrick’s Day parades began in North America in the 18th century but did not spread to Ireland until the 20th century.The participants generally include marching bands, the military, fire brigades, cultural organizations, charitable organizations, voluntary associations, youth groups, fraternities, and so on. However, over time, many of the parades have become more akin to a carnival. More effort is made to use the Irish language; especially in Ireland, where the week of St Patrick’s Day is “Irish language week”. Recently, famous landmarks have been lit up in green on St Patrick’s Day.