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I am making a tutorial about Emacs and do not know how to explain the reason why C-a is chosen as the keyboard to move the cursor to the beginning of a line?

Everything with C-b, C-f, C-n, C-p, C-e make sense for me, as they stand for backward, forward, next, previous, end

But why C-a stands for home?

My guess is that home can be understood as begin, but b is already used for backward, hence a, which stands before b, is chosen.

Does anyone know a better explanation?

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    unix.stackexchange.com/a/180113/56415 tries to address the historical side of this choice. – YoungFrog Aug 5 '17 at 22:15
  • This is just a guess, but I would imagine the reason being C-b (which would stand for "beginning of line") was already taken by "backward". – wvxvw Aug 6 '17 at 9:21
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a is at start of alphabet, and C-a moves to start of line (and mnemonic letters, e.g. s, were taken).

More importantly, it is a common command that can conveniently be typed with one hand, as a is on the left hand side of the keyboard near the control key. Ancient keyboards placed it just below TAB, where you might find Caps Lock nowadays.

In common sequences, left hand might type C-a or C-e, immediately followed by right hand typing C-o, RET, or prev / next arrows or control characters. It is good to make such a frequently used navigation command easy to type.

  • Thanks for your answer! @YoungFrog also gave a pointer to the history of C-a in bash – Trung Ta Aug 6 '17 at 8:06

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