Hack refers to a method that allows CSS to be perceived only by a specific browser.
Hacks can be used not only to fix bugs in the layout, but also if certain browser features are used to speed up the rendering of a web page in it (for example, CSS3 properties)
ALL KNOWN CONDITIONAL COMMENTS IN IE
Despite their fame, there are many rarely used ones.
For example, a stylesheet that will be visible to all browsers except IE versions 5-8. Continue reading