Comments

All programming languages allow the programmer to include comments in their code. To do this in R we use the # character.Anything to the right of the # sign and up to the end of the line is treated as a comment and is ignored by R. You can start lines with comments or include them after any code on the line.

area_hectares  <- 1.0  #  land  area  in  hectares  
area_acres  <- area_hectares  *  2.47  #  convert  to  acres  
area_acres  #  print  land  area  in  acres.  
[1]  2.47

Exercise

Create two variables my_length and my_width and assign them values. Create a third variable area and give it a value based on the current values of my_length and my_width. Show that changing the values of either my_length and my_width does not affect the value of area.