title: How do I intersect two data.frames in R?
body: <p>
  I have two tables that are in the data.frame structure. Table 1 contains a column of 200 gene IDs (letters and numbers) and Table 2 contains a list of 4,000 gene IDs (in rows) as well as 20 additional columns. I want to intersect these two tables and generate a new Table 3 that contains the 200 gene IDs as well as the associated information in the 20 columns.  </p>
  
  <p>
  table3 &lt;- table1%n%table2</p>