A bubble chart visualizes sales data for 19 employees, plotting cost of sales against profit, while bubble size encodes quantity sold and color distinguishes individual employees. The chart includes a legend for bubble size and a color legend. Built with D3.js v7, it uses `d3.scaleLinear` for axes and bubble size, `d3.interpolateTurbo` for colors, and SVG circles. Interactive tooltips display employee names on mouseover. Data is loaded from a local CSV file.