ChristmasorChristmasDay(OldEnglish:Crīstesmæsse,literally"Christ'smass")isanannualcommemorationofthebirthofJesusChrist,celebratedgenerallyonDecember25asareligiousandculturalholidaybybillionsofpeoplearoundtheworld.AfeastcentraltotheChristianliturgicalyear,itclosestheAdventseasonandinitiatesthetwelvedaysofChristmastide.Christmasisacivilholidayinmanyoftheworld'snations,iscelebratedbyanincreasingnumberofnon-Christians,andisanintegralpartoftheChristmasandholidayseason.

　　ManyofthepopularcelebratorycustomsassociatedinvariouscountrieswithChristmashavepre-Christianorsecularthemesandorigins.Popularmoderncustomsoftheholidayincludegift-givingandthehangingofChristmasstockings,Christmasmusicandcaroling,anexchangeofChristmascards,churchcelebrations,aspecialmealandvariousdeserts,andthedisplayofvariousdecorations,includingChristmastrees,Christmaslights,garlandsandwreaths,mistletoe,nativityscenes,Adventcalendarsandcandles,andholly.Inaddition,severalcloselyrelatedandofteninterchangeablefigures,knownvariouslyasSantaClaus,FatherChristmas,SaintNicholas,andKrisKringle,amongothernames,areassociatedwithbringinggiftstochildrenduringtheChristmasseasonandhavetheirownbodyoftraditionsandlore.Becausegift-givingandmanyotheraspectsoftheChristmasfestivalinvolveheightenedeconomicactivityamongbothChristiansandnon-Christians,theholidayhasbecomeasignificanteventandakeysalesperiodforretailersandbusinesses.TheeconomicimpactofChristmasisafactorthathasgrownsteadilyoverthepastfewcenturiesinmanyregionsoftheworld.

　　AspecialChristmasfamilymealistraditionallyanimportantpartoftheholiday'scelebration,andthefoodthatisservedvariesgreatlyfromcountrytocountry.Someregions,suchasSicily,havespecialmealsforChristmasEve,when12kindsoffishareserved.InEnglandandcountriesinfluencedbyitstraditions,astandardChristmasmealincludesturkeyorgoose,meat,gravy,potatoes,vegetables,sometimesbreadandcider.Specialdessertsarealsoprepared,suchasChristmaspudding,mincepiesandfruitcake.

　　ChristmascardsareillustratedmessagesofgreetingexchangedbetweenfriendsandfamilymembersduringtheweeksprecedingChristmasDay.Thetraditionalgreetingreads"wishingyouaMerryChristmasandaHappyNewYear",muchlikethatofthefirstcommercialChristmascard,producedbySirHenryColeinLondonin1843.Thecustomofsendingthemhasbecomepopularamongawidecross-sectionofpeoplewiththeemergenceofthemoderntrendtowardsexchangingE-cards.