This visualization displays the progression of COVID-19 total cases over time as a line chart with hover-based tooltips showing exact date and case counts. It loads data from a remote CSV via d3.csv and renders an SVG line using d3.line with linear and time scales. The chart includes axes from d3.axisBottom and d3.axisLeft, and interactive mouseover/mousemove handlers using d3.pointer and d3.bisector for nearest-point detection. The tooltip, styled as a separate HTML element, updates its position and text dynamically.