title: What is the use of 'sep' in paste command of R?
body: <p>I was working with the paste command in R, when I found that </p>
  
  <pre><code>a &lt;- c("something", "to", "paste")  
  paste(a, sep="_") 
  </code></pre>
  
  <p>produces the output </p>
  
  <pre><code># [1] "something" "to" "paste"
  </code></pre>
  
  <p>Which is same as when I <code>print</code> "a"</p>
  
  <pre><code># [1] "something" "to" "paste"
  </code></pre>
  
  <p>So what effect does the <code>sep</code> have on the <code>paste</code> command in R?</p>