Breakpoints.js is a jQuery plugin that makes modular responsive design possible by adding classes to elements based on defined breakpoints. Suppose you have a three versions of the block: “small”, “medium”, and “large” in a responsive design
. This block in a single column layout. It starts off at “medium”, then stretches to “large”, until eventually another column is introduced, and it goes to “small” because the column it is in is made smaller in order to fit the newly added column. This happens with each additional column with columns stretch.