Miles and miles of cables lie in the sea connecting continents and passing through various seas and oceans. It is a great task having these cables laid in the bottom of the sea. These same cables are used to also transfer telecommunications.
Early sea cables during the 19th century were made of iron and later replaced with steel wire. These cables were wrapped in India rubber and had multi-stranded copper wire at the core.
However, all the modern cables laid in the sea are made of fibre optic technology and are usually 69mm in diameter and are pretty heavy. Around 10Kg per metter. These carry digital payloads.
