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Arturo Espinoza
9,181 PointsWhen should I use an Id element and when should I use a classes element.
When should I use an Id element and when should I use a classes element.
4 Answers
Stephen Kiers
6,958 PointsIt depends on how you are using them. IDs and Classes have different functions depending on if you are using them for CSS or javascript. In practice, CSS doesn't care; javascript does. As Adam said, you can only have one ID per page, but you can reuse the same classes over and over. That is the simplest explanation, but there is more to it than that. I would go into detail, but css-tricks does a great job here : http://css-tricks.com/the-difference-between-id-and-class/
Adam Tatusko
16,589 PointsID's are unique and should only be used once per HTML page. Each element can have only one ID.
Classes are NOT unique. You can use the same class on multiple elements and you can use multiple classes on the same element.
George Elias
3,015 PointsID elements are unique and are use to target specific elements in CSS or Javascript. On the other hand, CLASSES can be repeated and should be used to apply the same styles to multiple elements.
Arturo Espinoza
9,181 PointsThank you for your replies. The link helped a lot with the examples.