[bckr]

That's not true though. The remainder of the text buffer is shifted. It really is a deletion and not an addition.

[ghodith]

I mean, that's true if you think of a space as exclusively a character. In the physical meaning of the word, what exists in place of the original character is now an empty 'space'. In some pedantic sense you have truly added space where there was once none.

[lloeki]

Consider the behaviour before or after either newlines in plaintext or paragraph ends in word processors. Also soft wrapping. It is truly a deletion now.