title: What are good examples of problems that graphs can solve better than the alternative?
body: <p>After reading Stevey Yegge's <a href="http://steve-yegge.blogspot.com/2008/03/get-that-job-at-google.html" rel="noreferrer">Get That Job At Google</a> article, I found this little quote interesting:</p>
  
  <blockquote>
    <p>Whenever someone gives you a problem, think graphs. They are the most fundamental and flexible way of representing any kind of a relationship, so it's about a 50–50 shot that any interesting design problem has a graph involved in it. Make absolutely sure you can't think of a way to solve it using graphs before moving on to other solution types. This tip is important!</p>
  </blockquote>
  
  <p>What are some examples of problems that are best represented and/or solved by graph data structures/algorithms?</p>
  
  <p>One example I can think of: navigation units (ala Garmin, TomTom), that supply road directions from your current location to another, utilize graphs and advanced pathing algorithms.</p>
  
  <p>What are some others?</p>