# What is the greatest determinant of the encoding of Morse code?

Anonymous January 7, 2014

I was reading a book “Code : the hidden language of hardware and software” and started learning and of course it’s an excellent book but I have a question that “why the letters and numbers are assigned to specific number of dots and dashes?” For example, the letter ‘a’ is taken as one dot and one dash, letter ‘b’ is taken as one dash and three dots, letter ‘c’ is taken as one dash, one dot, one dash and one dot etc. Thanks in advance.

1. Oron J
January 8, 2014 at 11:27 am

There are essentially three elements to the encoding of Morse code:
1. Efficiency (or compression). As Bruce explains, by using short codes for common symbols, the overall transmission is shorter.
2. Prevention of confusion. By having distinct codes for every symbol there's less chance of misreading (or mis-sending, for that matter) of the message.
3. Arbitrariness! At the end of the day, Mr. Morse designed the code and it was up to him to decide how to encode the characters. Arguably, someone else would have done it a little differently.

2. Bruce E
January 7, 2014 at 9:52 pm

As with most things, we strive for efficiency. One result of this is when encoding anything, the most frequently item to be encoded should be done in a manner to make it the most concise. Therefore, the most frequently used letter in the English language (E) was encoded by Morse to be a single dot. The whole thing ends up being an inversely related mapping between the shortest codes to the most used letters and the longest codes with the least used letters. Just remember that it is not the number of dots and dashes individually that determines the length of a letter's Morse code, but the total amount of time to key the letter (1 dot = 1 unit, 1 dash = 3 units, and the pause between the dots and dashes in a single letter = 1 unit, the pause between letters = 3 units, the pause between words = 7 units).

Many early compression algorithms did the same thing to encode alphabets.