A line chart animates between two datasets, updating its path shape over time. The example uses d3.line to generate the path from an array of numbers, mapping each value to x and y coordinates based on its index and magnitude. D3’s selection and transition methods handle the smooth morphing of the path’s `d` attribute when new data arrives. The SVG rendering is driven by a simple render function called twice with different data arrays, demonstrating a basic update pattern with d3.v5.