title: What is the difference between gc() and rm()
body: <p>I am periodically cleaning the memory in R using a call to <code>rm(list=ls())</code>.<br>
  Do I need to call the garbage collector <code>gc()</code> after that?</p>
  
  <p>What is the difference between these 2 functions? Does <code>gc()</code> call <code>rm()</code> for certain variables?</p>