Alexander Graham Bell

Alexander Graham Bell a Scottish-American inventor, scientist, professor, engineer.

 Pioneer of early metal detection technology.

Inventor of telephone.

Co-founder of the 'National Geographic Society'.

Co-founder of the 'Bell Telephone Company', which led to the creation of AT&T.

He was also part of the design team for a speedboat that later broke a world record.

The bel (B) and the smaller decibel (dB) are units of measurement of sound pressure level (SPL) invented by Bell Labs and named after him.