Both are different when they render
Label
Label control when rendered in browser gets converted to <SPAN /> tag
And if you set its AssociatedControlId property it gets converted to <LABEL /> tag.
Example Label with Text Mudassar the generated HTML would be
<span>Mudassar</span>
You can style a Label
Literal
Literal whatever you put will not be enclosed and will be rendered as is
Example Literal with Text Mudassar the generated HTML would be
Mudassar
You cannot style a Literal.