Basic Moving Point
To insert printing characters into the text you are editing, just type
them. This inserts the characters you type into the buffer at the
cursor (that is, at point; see Point). The cursor moves
forward, and any text after the cursor moves forward too. If the text
in the buffer is `
FOOBAR', with the cursor before the `
then if you type XX, you get `
FOOXXBAR', with the cursor
still before the `
To delete text you have just inserted, use
deletes the character before the cursor (not the one that the cursor
is on top of or under; that is the character after the cursor). The
cursor and all characters after it move backwards. Therefore, if you type
a printing character and then type
DEL, they cancel out.
To end a line and start typing a new one, type
inserts a newline character in the buffer. If point is in the middle of
RET splits the line. Typing
DEL when the cursor is
at the beginning of a line deletes the preceding newline, thus joining
the line with the preceding line.
Emacs can split lines automatically when they become too long, if you turn on a special minor mode called Auto Fill mode. See Filling, for how to use Auto Fill mode.
If you prefer to have text characters replace (overwrite) existing text rather than shove it to the right, you can enable Overwrite mode, a minor mode. See Minor Modes.
Direct insertion works for printing characters and
SPC, but other
characters act as editing commands and do not insert themselves. If you
need to insert a control character or a character whose code is above 200
octal, you must quote it by typing the character Control-q
quoted-insert) first. (This character's name is normally written
C-q for short.) There are two ways to use C-q:
RET, it serves only to terminate the sequence; any other non-digit is itself used as input after terminating the sequence. (The use of octal sequences is disabled in ordinary non-binary Overwrite mode, to give you a convenient way to insert a digit instead of overwriting with it.)
When multibyte characters are enabled, octal codes 0200 through 0377 are not valid as characters; if you specify a code in this range, C-q assumes that you intend to use some ISO Latin-n character set, and converts the specified code to the corresponding Emacs character code. See Enabling Multibyte. You select which ISO Latin character set though your choice of language environment (see Language Environments).
To use decimal or hexadecimal instead of octal, set the variable
read-quoted-char-radix to 10 or 16. If the radix is greater than
10, some letters starting with a serve as part of a character
code, just like digits.
A numeric argument to C-q specifies how many copies of the quoted character should be inserted (see Arguments).
DEL in most modes runs the command
RET runs the command
self-inserting printing characters run the command
which inserts whatever character was typed to invoke it. Some major modes
DEL to other commands.