JS user-defined properties of Objects

[awebguynow]

I'm actually trying to analyze the Google Suggest code
as dissected by C. Justus, eyalamir, alacrity and others.

This could be a follow-up to my unanswered posting:
Topic: "Google Suggest, advanced JS, DHTML" other keywords: okuh

But my ? this time is specific: Can properties of Objects be created
on the fly ?
Can they be user-defined (UD) and brought into existence, just by an
assignment ?

Ex:
M.completeDiv = _completeDiv;
or
var b = fr.completeDiv;
b.completeStrings = cs;
//b.displayStrings = ds;
//b.prefixStrings = pr;

I would say my level of knowledge is intermediate, but would like to
learn more.
If there are references online about this, please direct me to them.
Thanks.

[Richard Cornford]

awebguynow wrote:
<snip>

... Can properties of Objects be created
on the fly ?
Yes.
Can they be user-defined (UD) and brought into
existence, just by an assignment ?
That would depend on what you consider a 'user' in this context.
Executing javascript code can add properties to JS object with
assignments.

<snip> I would say my level of knowledge is intermediate, ...

You are being very optimistic.

Richard.