How do browsers treat images in CSS?

Cached or not?

[Wlauzon]

Most browsers will cache images in HTML, so that if the same image is used several times on a site it only has to download it once.

But how about images used in CSS, such as menu buttons?

IE7 seems to download each one again in a typical <ul> type list, but I see no way to check for sure, as the delay I see might just be the text.

[phranque]

check the server access logs.

[Jonesy]

Or, install the "Live HTTP Headers" addon for Firefox and check the headers on the client side.