What is CSS Reset?
A CSS Reset (or “Reset CSS”) is a short, often compressed (minified) set of CSS rules that resets the styling of all HTML elements to a consistent baseline. In case you didn't know, every browser has its own default 'user agent' stylesheet, that it uses to make unstyled websites appear more legible.
The goal of a reset stylesheet is to reduce browser inconsistencies in things like default line heights, margins and font sizes of headings, and so on.
Example for Css Reset
/* CSS Reset */
#element { margin:0; padding:0; font-size:100%; line-height:1; }
...
/* #element rules: */
#element { margin:5px 0 10px; font-size:13px; line-height:1.5; }
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