title: unzip a .zip file
body: <p>I want to unzip a file in R. I completely don't know what to do.</p>
  
  <p>I searched and I found it method like this : </p>
  
  <pre><code>unzip(zipfile, files = NULL, list = FALSE, overwrite = TRUE,
        junkpaths = FALSE, exdir = ".", unzip = "internal",
        setTimes = FALSE)
  </code></pre>
  
  <p>but I don't know what should I do with this.</p>