What is the difference between D3 and jQuery?

Question

Referring to this example:

http://vallandingham.me/stepper_steps.html

it seems that the D3 and jQuery libraries are very similar in the sense that they both do D

Answer 1

• D3 is data-driven but jQuery is not: with jQuery you directly manipulate elements, but with D3 you provide data and callbacks through D3's unique data(), enter() and exit() methods and D3 manipulates elements.

• D3 is usually used for data visualization but jQuery is used for creating web apps. D3 has many data visualization extensions and jQuery has many web app plugins.

• Both are JavaScript DOM manipulation libraries, have CSS selectors and fluent API and are based on web standards which makes them look similar.

Following code is an example of D3 usage which is not possible with jQuery (try it in jsfiddle):

  // create selection
  var selection = d3.select('body').selectAll('div');

  // create binding between selection and data
  var binding = selection.data([50, 100, 150]);

  // update existing nodes
  binding
    .style('width', function(d) { return d + 'px'; });

  // create nodes for new data
  binding.enter()
    .append('div')
    .style('width', function(d) { return d + 'px'; });

  // remove nodes for discarded data
  binding.exit()
    .remove();