What is the difference between the i and a commands of the vi editor?
i (interactive) requires the user to explicitly switch between vi modes whereas a (automatic) switches modes automatically.
i (insert) inserts text before the current cursor position whereas a (append) inserts text after the cursor.
i (independent rows) starts every new line at the first character whereas a (aligned rows) keeps the indentation of the previous line.
i (interrupt) temporarily suspends editing of a file to the background whereas a (abort) terminates editing.
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In vi, i enters insert mode before the cursor position, and a enters insert mode after the cursor position.
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