--- /dev/null
+
+@node Indentation, Text, Major Modes, Top
+@chapter Indentation
+@cindex indentation
+
+@c WideCommands
+@table @kbd
+@item @key{TAB}
+Indent current line ``appropriately'' in a mode-dependent fashion.
+@item @key{LFD}
+Perform @key{RET} followed by @key{TAB} (@code{newline-and-indent}).
+@item M-^
+Merge two lines (@code{delete-indentation}). This would cancel out
+the effect of @key{LFD}.
+@item C-M-o
+Split line at point; text on the line after point becomes a new line
+indented to the same column that it now starts in (@code{split-line}).
+@item M-m
+Move (forward or back) to the first non-blank character on the current
+line (@code{back-to-indentation}).
+@item C-M-\
+Indent several lines to same column (@code{indent-region}).
+@item C-x @key{TAB}
+Shift block of lines rigidly right or left (@code{indent-rigidly}).
+@item M-i
+Indent from point to the next prespecified tab stop column
+(@code{tab-to-tab-stop}).
+@item M-x indent-relative
+Indent from point to under an indentation point in the previous line.
+@end table
+
+@kindex TAB
+@cindex indentation
+ Most programming languages have some indentation convention. For Lisp
+code, lines are indented according to their nesting in parentheses. The
+same general idea is used for C code, though details differ.
+
+ Use the @key{TAB} command to indent a line whatever the language.
+Each major mode defines this command to perform indentation appropriate
+for the particular language. In Lisp mode, @key{TAB} aligns a line
+according to its depth in parentheses. No matter where in the line you
+are when you type @key{TAB}, it aligns the line as a whole. In C mode,
+@key{TAB} implements a subtle and sophisticated indentation style that
+knows about many aspects of C syntax.
+
+@kindex TAB
+ In Text mode, @key{TAB} runs the command @code{tab-to-tab-stop}, which
+indents to the next tab stop column. You can set the tab stops with
+@kbd{M-x edit-tab-stops}.
+
+@menu
+* Indentation Commands:: Various commands and techniques for indentation.
+* Tab Stops:: You can set arbitrary "tab stops" and then
+ indent to the next tab stop when you want to.
+* Just Spaces:: You can request indentation using just spaces.
+@end menu
+
+@node Indentation Commands, Tab Stops, Indentation, Indentation
+@section Indentation Commands and Techniques
+@c ??? Explain what Emacs has instead of space-indent-flag.
+
+ If you just want to insert a tab character in the buffer, you can type
+@kbd{C-q @key{TAB}}.
+
+@kindex M-m
+@findex back-to-indentation
+ To move over the indentation on a line, type @kbd{Meta-m}
+(@code{back-to-indentation}). This command, given anywhere on a line,
+positions point at the first non-blank character on the line.
+
+ To insert an indented line before the current line, type @kbd{C-a C-o
+@key{TAB}}. To make an indented line after the current line, use
+@kbd{C-e @key{LFD}}.
+
+@kindex C-M-o
+@findex split-line
+ @kbd{C-M-o} (@code{split-line}) moves the text from point to the end of
+the line vertically down, so that the current line becomes two lines.
+@kbd{C-M-o} first moves point forward over any spaces and tabs. Then it
+inserts after point a newline and enough indentation to reach the same
+column point is on. Point remains before the inserted newline; in this
+regard, @kbd{C-M-o} resembles @kbd{C-o}.
+
+@kindex M-\
+@kindex M-^
+@findex delete-horizontal-space
+@findex delete-indentation
+ To join two lines cleanly, use the @kbd{Meta-^}
+(@code{delete-indentation}) command to delete the indentation at the
+front of the current line, and the line boundary as well. Empty spaces
+are replaced by a single space, or by no space if at the beginning of a
+line, before a close parenthesis, or after an open parenthesis.
+To delete just the indentation of a line, go to the beginning of the
+line and use @kbd{Meta-\} (@code{delete-horizontal-space}), which
+deletes all spaces and tabs around the cursor.
+
+@kindex C-M-\
+@kindex C-x TAB
+@findex indent-region
+@findex indent-rigidly
+ There are also commands for changing the indentation of several lines at
+once. @kbd{Control-Meta-\} (@code{indent-region}) gives each line which
+begins in the region the ``usual'' indentation by invoking @key{TAB} at the
+beginning of the line. A numeric argument specifies the column to indent
+to. Each line is shifted left or right so that its first non-blank
+character appears in that column. @kbd{C-x @key{TAB}}
+(@code{indent-rigidly}) moves all the lines in the region right by its
+argument (left, for negative arguments). The whole group of lines moves
+rigidly sideways, which is how the command gets its name.@refill
+
+@findex indent-relative
+ @kbd{M-x indent-relative} indents at point based on the previous line
+(actually, the last non-empty line.) It inserts whitespace at point, moving
+point, until it is underneath an indentation point in the previous line.
+An indentation point is the end of a sequence of whitespace or the end of
+the line. If point is farther right than any indentation point in the
+previous line, the whitespace before point is deleted and the first
+indentation point then applicable is used. If no indentation point is
+applicable even then, @code{tab-to-tab-stop} is run (see next section).
+
+ @code{indent-relative} is the definition of @key{TAB} in Indented Text
+mode. @xref{Text}.
+
+@node Tab Stops, Just Spaces, Indentation Commands, Indentation
+@section Tab Stops
+
+@kindex M-i
+@findex tab-to-tab-stop
+ For typing in tables, you can use Text mode's definition of @key{TAB},
+@code{tab-to-tab-stop}. This command inserts indentation before point,
+enough to reach the next tab stop column. Even if you are not in Text mode,
+this function is associated with @kbd{M-i} anyway.
+
+@findex edit-tab-stops
+@findex edit-tab-stops-note-changes
+@kindex C-c C-c (Edit Tab Stops)
+@vindex tab-stop-list
+ You can arbitrarily set the tab stops used by @kbd{M-i}. They are
+stored as a list of column-numbers in increasing order in the variable
+@code{tab-stop-list}.
+
+ The convenient way to set the tab stops is using @kbd{M-x edit-tab-stops},
+which creates and selects a buffer containing a description of the tab stop
+settings. You can edit this buffer to specify different tab stops, and
+then type @kbd{C-c C-c} to make those new tab stops take effect. In the
+tab stop buffer, @kbd{C-c C-c} runs the function
+@code{edit-tab-stops-note-changes} rather than the default
+@code{save-buffer}. @code{edit-tab-stops} records which buffer was current
+when you invoked it, and stores the tab stops in that buffer. Normally
+all buffers share the same tab stops and changing them in one buffer
+affects all. If you make @code{tab-stop-list} local in one
+buffer @code{edit-tab-stops} in that buffer edits only the local
+settings.
+
+ Below is the text representing ordinary tab stops every eight columns:
+
+@example
+ : : : : : :
+0 1 2 3 4
+0123456789012345678901234567890123456789012345678
+To install changes, type C-c C-c
+@end example
+
+ The first line contains a colon at each tab stop. The remaining lines
+help you see where the colons are and tell you what to do.
+
+ Note that the tab stops that control @code{tab-to-tab-stop} have nothing
+to do with displaying tab characters in the buffer. @xref{Display Vars},
+for more information on that.
+
+@node Just Spaces,, Tab Stops, Indentation
+@section Tabs vs. Spaces
+
+@vindex indent-tabs-mode
+ Emacs normally uses both tabs and spaces to indent lines. If you prefer,
+all indentation can be made from spaces only. To request this, set
+@code{indent-tabs-mode} to @code{nil}. This is a per-buffer variable;
+altering the variable affects only the current buffer, but there is a
+default value which you can change as well. @xref{Locals}.
+
+@findex tabify
+@findex untabify
+ There are also commands to convert tabs to spaces or vice versa, always
+preserving the columns of all non-blank text. @kbd{M-x tabify} scans the
+region for sequences of spaces, and converts sequences of at least three
+spaces to tabs if that is possible without changing indentation. @kbd{M-x
+untabify} changes all tabs in the region to corresponding numbers of spaces.
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