Six horizontal bars form an editable bar chart, with each bar implemented as a draggable D3 v4 brush selection. The chart displays six numeric values between 0 and 20, rendered as blue bars on a light yellow background with a black axis. Users adjust a bar’s height by dragging its brush handle horizontally, which updates the underlying data and the white text label showing the value. The visualization uses `d3.brushX()` for interaction, `d3.scaleLinear()` for positioning, and SVG rendering, with the brush extent constrained to each bar’s row.