Difference between Class and ID selectors?

I can't seem to work out how they are different. Probably a stupid question, but hey, I'm a stupid sort of person.

Thanks.

 

In the CSS, a class selector is a name preceded by a full stop (.) and an ID selector is a name preceded by a hash character (#).

The difference between an ID and a class is that an ID can be used to identify one element, whereas a class can be used to identify more than one.

You can also apply a selector to a specific HTML element by simply stating the HTML selector first, so p.jam { whatever } will only be applied to paragraph elements that have the class 'jam'.

 

Think of a Class as being able to describe an object, where as an ID is describing a specific object.

For instance, an SUV is a Class of Automobiles...so is Truck, however a Toyota Tundra identifies a truck name. So when telling someone you want a red Toyota Tundra, then you use ID. But when you tell someone you like red automobiles then you use CLASS. Lord I was born a RAMBLING man...

 

You know what, I almost get that! Thanks!

So, let's see if I've got this right...

Say I have a class with no tag such as:

.lookscool { something cool }

I could have <h1 class="lookscool"> and <p class="lookscool">
Whereas with ID, it can only be <h1> OR <p> or whatever else.

So is

p.lookscool { coolness }
<p class="lookscool">

and

#lookscool { coolness }
<p id="lookscool">

the same thing?

And you can't go:
#lookscool { coolness }
<p id="lookscool">
<h1 id="lookscool">
right?

Ok, I hope I've got that right, thanks.

 

Yup. An ID value can only be used once on a page (example: <div id="myID"></div> and <div id="yourID"></div> are legal, but having two elements, whether a pair of DIVs or a DIV and a P, or even a P and a SPAN with id="myID" are not), but a class can be used over and over.

As with the second part of the previous example (<div id="myID"></div> and <div id="myID">) replace the ID with class and you're golden.