# Browser Prefixes

• When browser companies want to add a trial version of a CSS property they add support for a prefixed version.
• Each browser engine has it's own prefix.
• If you want to support older browsers then you add the prefixed version of the property first and then the non-prefixed version last.
• Not all properties have a prefixed version for each browser, or at all.

/* demo version of the prefixes */
-moz-border-radius: 12px;
-webkit-border-radius: 12px;
-o-border-radius: 12px;
-ms-border-radius: 12px;