====== diff ======

  $ cat ejemplo1.txt
  
  John Smith 	1001 	Sr. Engineer
  Peter		1002	Engineer
  Fernandous	1003	Sr. Engineer
  Kraml		1004	Jr. Engineer
  
  $ cat ejemplo2.txt
  
  John Smith 	1001 	Sr. Engineer
  Peter		1002	Engineer
  Fernandous	1003	Resigned
  Kraml		1004	Jr. Engineer
  Raj		1005	Engineer

  * diff
  * colordiff
  * wdiff
  * dwdiff
  * meld



====== patch ======

  $ diff -u ejemplo1.txt ejemplo2.txt > ejemplo.patch
  $ patch < ejemplo.patch 
  $ diff -u ejemplo1.txt ejemplo2.txt
  $ patch -R < ejemplo.patch
  $ diff -u ejemplo1.txt ejemplo2.txt