FlowType JS dynamically resizes and reflows text within any element

What does FlowType.JS do?. Ideally, the most legible typography contains between 45 and 75 characters per line. This is difficult to accomplish for all screen widths with only CSS media-queries. FlowType.JS eases this difficulty by changing the font-size and subsequently the line-height based on a specific element’s width. This allows for a perfect character count per line at any screen width.