title: retrieving .json object and storing it in variables
body: <p>My .json file is:</p>
  
  <pre><code>{
  "links":[
    {source: "algorithms cormen", target: "irodov", type: "default"},
    {source: "algorithms cormen", target: "skienna", type: "default"},
    {source: "irodov", target: "skienna", type: "default"},
    {source: "irodov", target: "algorithms cormen", type: "default"}
  ],
  "data":[
      {node: "algorithms cormen", data: "bible of algos"},
      {node: "irodov", data: "bibile of physics"},
      {node: "skienna", data: "cool book"}
  ]
  }
  </code></pre>
  
  <p>Now in my javascript file, I want the data stored by "links" to go to a links variable. The same thing I want to do with the "data"
  How do I achieve this? I am using d3.js library, so if there is some function included in this library which I can use, mention them.</p>