On Ubuntu . show output Any Unix extension you use must have a log file, which store the system activity in some kind of a log file/files, please pick two different "Time" of any log file you have in your system, analyze and decode it in a simple English. Example: you rebooted your machine or added new user or any other activity that you might do normally. What do you see on the log file after your activity? Post the sections of your log file that you see changes. Point out those changes.