The first day of the week in Europe and in systems using the ISO 8601 norm and second day of the week in the USA. In Middle Eastern countries the beginning of the workweek is usually Saturday (Thursday and Friday are observed as the weekend). In Israel, Sunday is the first day of the workweek. Friday is half a work day and Friday night and Saturday are the Sabbath.
The word for Monday is derived via the ancient Anglo-Saxon/Germanic tongue from the word for Moon, "monandaeg". Most other Western and Southern European languages use their own derivative of the word, "moon", as a root for "Monday". For example, the Latin word for moon is "luna" and from that comes the French word "Lundi".
Monday has often been called a blue day. There is considerable speculation as to why this might be so. One theory runs that Monday (before the advent of the washing machine) was the usual day for washing and a blue dye was frequently used to keep clothes from yellowing. Blue is also frequently associated with depression. Since Monday is typically the first workday of the week and workers must look over a long depressing stretch of time until their next day-long break it has often been refered to as a blue day.
Many cultures see Monday also as an unlucky day, even as a day when people become insane. This may have something to do with the day's association with the moon. The moon has been called inconstant, due to its tendency to wax and wane. The Latin word for moon comes even into our own language to designate lunacy.
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