xargs is an UNIX command. When should you use xargs? When the output of a command is the command-line options of another command, use xargs in conjunction with pipes. When the output of a command is the input of another command, use pipes.

Example: 

find . -type f -mtime -1 -print|xargs pr -n |lp

With no options, xargs reads standard input, but only writes enough arguments to standard output as to not overflow the command-line buffer. Thus, if needed, xargs forces multiple executions of pr -n|lp.

Another example: remove all files with a txt extension 

find . -type f -name "*.txt" -print|xargs rm

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