Morse code is a method for transmitting telegraphic information,
using standardized sequences of short and long elements to represent
the letters, numerals, punctuation and special characters of a message.
The short and long elements can be formed by sounds, marks or pulses,
and are commonly known as "dots" and "dashes"
or "dits" and "dahs".
For much of the twentieth century, the majority of high-speed international communication was conducted in Morse code, using telegraph lines, undersea cables, and radio links. However, the variable length of the Morse characters made it hard to adapt to automated links, so for most electronic communication it has been replaced by more regular formats, including the Baudot code and ASCII.
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Here is how morse code look like for - www.livephysics.com
.-- .-- .-- .-.. .. ...- . .--. .... -.-- ... .. -.-. ... -.-. --- --