Why Bluetooth and how it got its name:

Harald “Bluetooth” Gormsson was a king of Denmark and Norway. He was the son of King Gorm the Old and of Thyra Dannebod. Harald ruled as king of Denmark from c. 958 – c. 986. Harald introduced Christianity to Denmark and consolidated his rule over most of Jutland and Zealand. Wikipedia

(910–c. 987), otherwise known as King Harald I of Denmark, was best known for three major achievements. First, he completed the work of unifying Denmark under a single ruler. Second, he conquered Norway—an event which had major historical consequences.

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Bluetooth Harald