indentation, setting variables, commands, and M-x

[John M. Gabriele]

Hi, I've just started to learn emacs, and would like to try
using it as my primary editor/IDE, but first need to get a few
things set up. For one thing, the indentation issue.

I'd like to only get spaces in my files, 4 for each level of
indentation, and also have the autoindent work (filling in
spaces as necessary). That is, when I hit the TAB key, I want
to get enough spaces to the next indent-level, filling in
spaces along the way.

I just read here: http://www.emacswiki.org/cgi-bin/wiki/NoTabs
that I can add this

    (setq-default indent-tabs-mode nil)

to my .emacs file (which I haven't yet created). That page says
I can "customize the indent-tabs-mode variable". What does that
mean exactly? How do I go about "customizing" it?

I'm also curious: what's the translation between adding the
above line to my .emacs, and typing something in while editing
(presumably "M-x something")? That is, if someone tells me a
line to add to my .emacs file, how can I figure out how to do
the same thing from within the editor while editing?

Continuing with the indentation issue, I read here:
http://www.emacswiki.org/cgi-bin/wiki/IndentationBasics that
there's a number of "variables" I can set. I see "tab-width"
there. Yay! That looks like what I want. :) But, again, how
do I "set a variable" for emacs (both in my .emacs file,
and live, while editing)?

Regarding the autoindent, Reading here:
http://www.emacswiki.org/cgi-bin/wiki/AutoIndentation it
sounds like autoindent isn't something that comes free, but
instead, to get it, you have to put a one-liner into your
.emacs file. Seems like maybe something that should be
default behaviour, no?

Thanks!
---J

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