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:
“Painting consumes labour not disproportionate to its effect; but a fellow will hack half a year at a block of marble to make something in stone that hardly resembles a man. The value of statuary is owing to its difficulty. You would not value the finest head cut upon a carrot.”
—Samuel Johnson (1709–1784)