I am having trouble understanding the difference between using classes and ids. Could anyone help me out.

Although most of those who practice CSS don't pay attention to it, the difference between the ID and CLASS selectors is very simple.

CLASS selectors may be used as many times as possible on a page; however, ID is a unique tag that may only be used once per page. Although, you will find others who use them both the same way, that isn't the correct practice of HTML/XHTML.

Also with classes, you can do things like p.classname, which would identify all P tags that had "classname" as their CLASS.

I hope this helps you out.

thanks that helped me alot.

Wow. I had no idea. So, in my pages, would everything still render correctly if I changed all of my <div id=> tages to <div class=> tags when they are used more than once?

Originally Posted by lynnema

Wow. I had no idea. So, in my pages, would everything still render correctly if I changed all of my <div id=> tages to <div class=> tags when they are used more than once?

Yes, everything should look the same if you change your IDs to classes. It is really best to just use an ID once (per document) and use classes for things that appear more than once.

An id is primarily targeted for javascript, in my mind.
It allows you to put a tag on a particular element of the page, to access it later and alter it state dynamically.

Not too, although I don't think many people knows that, that you can put multiples classes on an element:

<div class="bold noPadding red">
sgdgf
</div>

will apply all the 3 classes, in the order they are specified, on the content of the div.

On contrario, an element cannot have multiples Id.

Thank You for the help i now understand the difference between the two

I'm glad that you found that of use.