is it important to use the class="" in my html code linked to my css cod?

Answer 1

You can use a class to apply a style to a group of content that share the same style, instead you can use an id if you want to apply a style just for one element

Answer 2

I second that answer.

Answer 3

Not only classes and ids, but also generic tags such as <p>.

Answer 4

Classes are used to define different parts of the pages. You can use the same class more then 1 time and you can use unlimited classes.