La commande date affiche la date.
(output de la commande tldr date)
Wiki étudiants INGI
date +"%c" : Display the current date using the default locale's format
date -u +"m-H:SZ" : Display the current date in UTC and ISO 8601 format
date +%s : Display the current date as a Unix timestamp (seconds since the Unix epoch)
date -d @1473305798 : Display a specific date (represented as a Unix timestamp) using the default format
date -d "{{2018-09-01 00:00}}" +%s --utc : Convert a specific date to the Unix timestamp format
man date