Thursday (/ˈθɜrzdeɪ/ or /ˈθɜrzdi/) is the day of the week following Wednesday and before Friday. According to the ISO 8601 international standard adopted in most western countries, it is the fourth day of the week. In countries that use the Sunday-first convention, Thursday is defined as the fifth day of the week. It is the fifth day of the week in the Judeo-Christian liturgical calendar.