Let's look at building a new file to practice using regular expressions. In this example, we will use grep in conjunction with the . and * REs. Since REs will specify a method of matching, I will attempt to drive home the concept of REs with a search through a simple text file that you can create with the vi editor or emacs.
Make a file that has the current information within it:
Rob's Test File Rob Shimonski "aka Unix junkie" 2006 2005 2004 2003 2002 2001 2000 1999 1899
Once you have finished, save and name the file robtest.txt.
This file will serve as the data we will search to learn how to use REs. In this example, we will use the period (.), which can be used to match any character as a single unit, and the asterisk (*), which ...