Why Are There Asterisks Before Some CSS Properties?

Understanding the Purpose of Asterisks Before CSS Properties

In the realm of CSS, you may have encountered asterisks (*) prefixed before certain property names. These asterisks play a specific role, particularly in the context of Internet Explorer versions 7 and below.

The Role of Asterisks in CSS Hacks

CSS hacks are techniques used to target specific browsers or versions of browsers while avoiding their impact on others. By placing an asterisk before a property name, you can create a CSS rule that applies only to Internet Explorer versions 7 or below.

Example Usage

Consider the following example:

body {
  font:13px/1.231 arial,helvetica,clean,sans-serif;
  *font-size:small;
  *font:x-small;
}

In this example, the asterisks prefixing the font-size and font properties ensure that these properties are applied only in Internet Explorer versions 7 or below.

Implications of Using Asterisks in CSS

While CSS hacks can be useful in certain situations, it's important to note their potential drawbacks:

• Invalid CSS: The use of asterisks as a property prefix is not part of the CSS specification. This means that it could result in unexpected behavior in future versions of browsers.
• Potential for Conflicts: If you use asterisks in CSS hacks, it may conflict with other CSS rules in your code or third-party stylesheets.
• Limited Support: Asterisks only work in Internet Explorer versions 7 or below. Therefore, they have no effect on modern browsers.

Alternatives to Asterisk Hacks

In place of asterisk hacks, consider using media queries or browser-specific class names to target different versions of Internet Explorer or other browsers. These methods are more standardized and maintain the validity of your CSS.

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