This stacked bar chart visualizes the gender distribution of students across university modules, with bars representing counts of males and females for each course. Users can toggle between absolute counts and percentage-based views via radio buttons, which recalculates the stack layout with d3.layout.stack and triggers smooth transitions. Built with D3.js version 3.5.6, the chart loads data from a CSV file and renders as SVG, featuring rotated x-axis labels and a color-coded legend to distinguish genders.