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HTML How to Make a Website Debugging HTML and CSS Problems How to Fix Problems with Code

Posted by Niger Hall
Niger Hall
3,800 Points

Class and ID

How do you know when to use class as opposed to id and vic versa?

3 Answers

Christian Andersson
Christian Andersson
8,712 Points

Generally, you should use a class when you are referring to an item type, where as ids should only be used when referring to a single and specific entity.

A class can be referred to in your html several times, where as an id can only be used once, so you should use classes for items that you know you're going to use a lot. An example would be if you wanted to give all the paragraphs on your webpage the same styling, you would use classes. If you then decided that, out of all these paragraphs, you want to give the very first paragraph a special style, you would use an id on just the first paragraph.

So id for one (or a few), and class for many.

Ryan Carson
Ryan Carson
23,287 Points
Ryan Carson
Ryan Carson
23,287 Points

IDs should only be used once. Classes can be used many times :)

Gard Mikael Fjeldavli
Gard Mikael Fjeldavli
19,416 Points
Gard Mikael Fjeldavli
Gard Mikael Fjeldavli
19,416 Points

That's really up to you. BUT; an ID can only be assigned to one element, while you can give many elements the same class. So if you are designing your website and want to give (for example) all your submit buttons the same look, you might give them all the same class, so the same styles will be applied to all your buttons. But if you want to target only one of them, you might give it an ID, and the styles you bind to this ID will only apply to that ID. =)