title: How to combine 2 plots (ggplot) into one plot?
body: <p>By using R, is it possible to place 2 ggplot together (i.e., on the same plot)? I wish to show a trend from 2 different data frames and instead of putting them one next to the other, I'd like to integrate them together in one plot and only to change the color of one of them (the black dot).</p>
  
  <p>To be more specific, I have the following 2 visuals:</p>
  
  <pre><code>ggplot(visual1, aes(ISSUE_DATE,COUNTED)) + geom_point() + geom_smooth(fill="blue", colour="darkblue", size=1)
  </code></pre>
  
  <p>and</p>
  
  <pre><code>ggplot(visual2, aes(ISSUE_DATE,COUNTED)) + geom_point() + geom_smooth(fill="red", colour="red", size=1)
  </code></pre>
  
  <p>They look like this (both have black dots and I'll need to change one of them to something different):</p>
  
  <p><img src="https://i.stack.imgur.com/sDdJm.png" alt="enter image description here"></p>
  
  <p>and</p>
  
  <p><img src="https://i.stack.imgur.com/DBNLZ.png" alt="enter image description here"></p>