I discovered a file reset.css in one of our Project's css folder. I went ahead googling the purpose of this file and found it's interesting use. Browsers as we all know are different in their interpretation of certain things. Default line-heights, margins font-sizes being some of them. What this means is that a header on your IE would not be exactly same in appearance in your chrome or firefox.
Reset Stylesheet is used to handle these discrepancy. It is included as the top css in your project and has style rules that will make default styles same on all the browsers. Helping you achieve a consistent look of your site across browsers. The link below takes you to original explanation http://meyerweb.com/eric/tools/css/reset/