Bluetooth is named after a 10th century Danish Viking king called Harald Blåtand. Of course his name has been anglicised to Harold Bluetooth, which I find a bit silly. To me Harald is the name of a tough ravaging viking, while Harold is a middle aged semi-bald English guy sitting in an armchair with slippers on his feet, reading his newspaper while puffing away on a pipe (married to a woman called Maude).
No matter, Bluetooth was named so because Harald Blåtand through diplomacy convinced different factions to negotiate peace with each other, which probably made his job as king a bit easier, it's not always "Good to be the King".
This is what Bluetooth does for wireless connections between phones, computers, cars, headsets and what have you, it makes all those devices, that conform with the Bluetooth standard, negotiate and talk to each other making your life easier.
As soon as I start my car my phone is automatically hooked into the car-kit, I don't even have to remove the phone from my pocket. On the street you see people with bluetooth earpieces hanging in their ears, oblivious to how silly they look. It's nothing new though, Uhura from Star Trek had a bluetooth earpiece before anyone else.
Now I'm just waiting for people to wake up to the fact that the other wireless standards have also been named for Danish kings, namely the Triplet Kings; IEEE 802.11a, IEEE 802.11b and IEEE 802.11g.
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