Hello!

Can you tell me what is the CSS invisibility setting for? In what cases is it used? Why you should hide something when you can just not write it?

Thanks,
eyedam

The visibility property is most likely used with DHTML. You might use it when, for example, someone clicks on something on your page and using Javascript you can choose to hide/show that element. Since invisible items on a page still take up space on the page, use of the 'display' property is more common.

All the menus you see on this forum ('Search this Thread', 'Rate Thread', 'Quick Links' and collapsing forums etc) all use the 'display' property combined with Javascript to do the dirty work.

OK, thanks for the answer! I didn't think of that.

But then still "invisibility" option is rarely used, but "display" is used instead?

Can I use "invisibility" or "display" option also for hidden links that I don't want the people to see but for the search spiders to read and follow?

eyedam

Yes, but Google discourages you from doing that.

http://www.google.com/webmasters/guidelines.html

Goto the final bulleted list.

Basic rule of thumb is, if it's purpose isn't for your users, then don't put it in at all

Originally Posted by eyedam

But then still "invisibility" option is rarely used, but "display" is used instead?

Well, there are probably certain times where you'd like to show/hide elements of a page but need them to take up space to retain the "shape" of the layout. That's one example that comes to my head.