There are several tools that are useful when submitting commands to the kernel via the shell. These tools help make tasks more efficient. One such tool is the wild card.
The wild cards that you will use most often include the asterisk (*), the question mark (?) and the brackets ()
The asterisk is used to match any character zero or more times. For example, if we modify the "ls" command used in the last section, we can filter the output for only files starting with "s" using the command ls -l s*
The question mark on the other hand, is used to match any single character. Thus ls -l ???? will match any file with a name four characters long such as temp or "temp"
Finally, brackets are used to specify ranges or internal sets. Thus you can specify which characters from within a set you are looking for such as in the following case which matches any even number below 10: 
Below is a table that shows some of the more common uses for wildcards with the "ls" command that you might use