UUOC [from the comp.unix.shell group on Usenet] Stands for `Useless Use
   of {cat}'; the reference is to the Unix command cat(1), not the feline
   animal. As received wisdom on comp.unix.shell observes, "The purpose of
   cat is to concatenate (or `catenate') files. If it's only one file,
   concatenating it with nothing at all is a waste of time, and costs you a
   process." Nevertheless one sees people doing

  cat file | some_command and its args ...
  
   instead of the equivalent and cheaper

  Source: The Jargon File