Underscore Hack
Versions 6 and below of Internet Explorer recognize properties with this prefix (after discarding the prefix). All other browsers ignore such properties as invalid. Therefore, a property that is preceded by an underscore or a hyphen is applied exclusively in Internet Explorer 6 and below.
#elem { width: ; _width: ; }This hack uses invalid CSS and there are valid CSS directives to accomplish a similar result. Thus some people do not recommend using it. On the other hand this hack does not change the specificity of a selector making maintenance and extension of a CSS file easier.
Read more about this topic: CSS Filter
Famous quotes containing the word hack:
“I was gonna call it “I Love You, Samantha” but some old hack got there before me.”
—Blake Edwards (b. 1922)