This example demonstrates a range of JavaScript array operations, including mapping, reducing, sorting, and transforming data with the D3.js library (version 6.6.2). The code creates numeric ranges, generates random values, and applies calculations like squaring and doubling to each element, logging the results to the console. It also shows how to sort an array of objects by key using d3.ascending, and uses reduce to accumulate a Fibonacci-style sequence while printing each addition step. The visualization relies entirely on console output, with no graphical rendering.