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(emacs-lisp-intro.info)Using setq

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Using `setq'
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   As a practical matter, you almost always quote the first argument to
`set'.  The combination of `set' and a quoted first argument is so
common that it has its own name: the special form `setq'.  This special
form is just like `set' except that the first argument is quoted
automatically, so you don't need to type the quote mark yourself.
Also, as an added convenience, `setq' permits you to set several
different variables to different values, all in one expression.

   To set the value of the variable `carnivores' to the list `'(lion
tiger leopard)' using `setq', the following expression is used:

     (setq carnivores '(lion tiger leopard))

This is exactly the same as using `set' except the first argument is
automatically quoted by `setq'.  (The `q' in `setq' means `quote'.)

   With `set', the expression would look like this:

     (set 'carnivores '(lion tiger leopard))

   Also, `setq' can be used to assign different values to different
variables.  The first argument is bound to the value of the second
argument, the third argument is bound to the value of the fourth
argument, and so on.  For example, you could use the following to
assign a list of trees to the symbol `trees' and a list of herbivores
to the symbol `herbivores':

     (setq trees '(pine fir oak maple)
           herbivores '(gazelle antelope zebra))

(The expression could just as well have been on one line, but it might
not have fit on a page; and humans find it easier to read nicely
formatted lists.)

   Although I have been using the term `assign', there is another way of
thinking about the workings of `set' and `setq'; and that is to say
that `set' and `setq' make the symbol _point_ to the list.  This latter
way of thinking is very common and in forthcoming chapters we shall
come upon at least one symbol that has `pointer' as part of its name.
The name is chosen because the symbol has a value, specifically a list,
attached to it; or, expressed another way, the symbol is set to "point"
to the list.