How can I turn on line numbering in Vi?

Sometimes it is useful to view line numbers when editing a file, and especially when coding. To turn on this numbering in the vi editor, type this:

:set number

(enter)

You should see something like this in your editor:



      1 .text {
      2         font-family: Arial, Helvetica, sans-serif;
      3         font-size: 12px;
      4 }
      5 .green_text {
      6         font-family: Arial, Helvetica, sans-serif;
      7         font-size: 12px;
      8         font-weight: bold;
      9         color: green;
     10 }
     11 h3 {
     12         font-family: Arial, Helvetica, sans-serif;
     13         font-size: 16px;
     14 }

To turn off the numbering, simply type:

:set nonumber

(enter)