Do your images slow down your site?
You can make your pages load more quickly by making sure you
include the height and width attribute in all your image tags,
like this:
Now the browser knows exactly how much space to leave when
drawing the page on the screen. If a page has several graphics,
and you don't specify their size, the browser will download the
page, then the pictures. Now what? It discovers it hasn't left
enough room for picture number one, so it has to re-draw the
page on the screen. Next picture - same problem! Another page
re-draw. And so on, right through your page.
Any visitors on a slow connection, or with a slower PC, may
simply give up and move on to another site.
What does that "alt" attribute do? If you put your cursor over a
picture and leave it there for a moment, you'll see the contents
of the "alt" attribute that the webmaster has used for this
picture. It's handy for giving visitors information such as
"Click to go to ..." or "Download here".
It's also essential for visitors using text-only browsers. Are
there any? Yes - plenty of blind or partially sighted web-users
have them, and without an "alt" they won't know what the picture
is about. If it is a "clickable" picture, linking to another
part of your site, or to a download, they won't be able to
access it.
Also, many users surf with the pictures turned off, to speed up
page downloads. All they will see is an empty square - your
"alt" will tell them what they're missing.