it does not draw visualizations • D3 = "Data Driven Documents"; it primarily associates data with DOM elements and manages the results • D3.js also provides tools that you can use to draw visualizations
does add 25 circles to the page, it's not taking advantage of D3.js nodes.forEach(function(node) { svg.append("circle"); }); There's a better approach...
a physical world with forces such as gravity and electromagnetism • Elements given properties that correspond to mass and charge • Positions elements in reaction to simulated physical forces