Building content for the web you start up with some skeletons, like the fundament on a house. Many such skeletons – or frameworks – exists, each of them offers many building blocks allowing you to build your website.
The part of a webpage which is used to style or layout websites is called CSS: Cascading Style Sheet. Some of them require a minimum version of a given browser to work. Like Microsoft Internet Explorer 8 or Firefox 3.
This page CSS FRONTEND FRAMEWORKS offers you an overview of the different frameworks around, so go visit this site to see some of the features and requirements for many CSS frameworks.