This example demonstrates how to render a simple line chart with D3.js, plotting five data points that form a gentle, non-monotonic curve. The visualization builds a path element using the `d3.line` generator, which maps x- and y-coordinates through scales to position the line within the SVG. The line is styled with a steelblue stroke, no fill, and is appended directly to an SVG container. The code relies on the core D3 v3 API, including the `line()` generator and append/datum methods, without any additional libraries or interactive behaviors.