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General Discussion

Posted by Colby Work
Colby Work
20,422 Points

ID's or Classes?

Peace, fam!

I see a lot of people using classes over ID's, and have wondered for a long time, what the best practice is for choosing one over the other? I know an ID is for an element that appears once on a page, so why would people do things like:

h1 class="site-title" (when site title only is on each page once)

or even regions like class="main", when main is a section that only appears one time. Is it preference? Because to me, it doesn't make sense to ONLY use classes, especially knowing that classes are for elements that appear more than once.

I wish I had more specific examples, but this is just something I've noticed for a while now and haven't found a decent explanation yet.

5 Answers

notf0und
notf0und
11,940 Points
notf0und
notf0und
11,940 Points

ID's are unique: Each element can have only one ID Each page can have only one element with that ID

Classes are NOT unique You can use the same class on multiple elements. You can use multiple classes on the same element.

http://css-tricks.com/the-difference-between-id-and-class/

Colby Work
Colby Work
20,422 Points
Colby Work
Colby Work
20,422 Points

Thanks Bryan H, I understand the difference, but I was wondering why some would choose to use classes where ID's are more appropriate.

notf0und
notf0und
11,940 Points

For the possibility that they may use the class again, and don't want to use an ID which they may have to go back and change . So essentially: personal preference based on the limitations of IDs.

Danny Carrillo
Danny Carrillo
819 Points
Danny Carrillo
Danny Carrillo
819 Points

I only use IDs to wrap content, for example, a header, or footer. Easier to manipulate in CSS

Don Brubaker
Don Brubaker
2,518 Points
Don Brubaker
Don Brubaker
2,518 Points

I think it really just comes down to a choice of programming style, for each person. Would be my best guess.

Adam Fichman
Adam Fichman
9,502 Points
Adam Fichman
Adam Fichman
9,502 Points

While I'm not saying I essentially agree with everything in the article, here is a great article on the thought process behind using classes over ideas from css wizardy