When do you use "id" and "class"? In other words, which tags should I include the above?

Answer 1

Id can be used to identify one element, whereas a class can be used to identify more than one.

Answer 2

Id represents as #idname
Class represents as . classname

Answer 3

「ＨＡＰＰＹ ＴＯ ＨＥＬＰ」 I'd like to add onto your answer by saying that IDs have a higher precedence than classes.

Answer 4

any body online, please?