Sto lat

"Sto lat" (One Hundred Years) is a traditional Polish song that is sung to express good wishes, good health and long life to a person. It is also a common way of wishing someone a happy birthday in Polish.

The song's author and exact origin are unattributed. The song is sung both at informal gatherings (such as birthdays or name days) or at formal events, such as weddings. Frequently, the song "Niech im gwiazdka pomyślności" will be sung afterwards, excluding kids' parties, as the song makes reference to alcohol consumption. At state events it is not unusual to hear it performed by an orchestra or a military band. It is also noted for being an integral part of Polish immigrant culture even long after assimilation.

The song serves the equivalent function of "Happy Birthday to You" or "For He's a Jolly Good Fellow".

This translates roughly into English as:

The phrase "Sto lat!" is also often used to wish someone longevity or good fortune, or as a toast, without the song. However, the use of "Sto lat!" in this manner will often lead to the song being sung by those present. The phrase is also sometimes used to acknowledge someone's sneezing - similarly to "God bless you", though for that particular occasion a simple na zdrowie ("To your health") is more frequently used.

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Wikipedia