all date format in linux shell script code example

Example: bash date variable format

# Source: https://www.tutorialkart.com/bash-shell-scripting/bash-date-format-options-examples/
date '+<format-option><format-option> <format-option>'
# For example:
echo $(date '+%A')
date=$(date '+%A')

# Formats:
# date +%a	Weekday	Name of weekday in short (like Sun, Mon, Tue, Wed, Thu, Fri, Sat)	Mon
# date +%A	Weekday	Name of weekday in full (like Sunday, Monday, Tuesday)	Monday
# date +%b	Month	Name of Month in short (like Jan, Feb, Mar )	Jan
# date +%B	Month	Month name in full short (like January, February)	January
# date +%d	Day	Day of month (e.g., 01)	04
# date +%D	MM/DD/YY	Current Date; shown in MM/DD/YY	02/18/18
# date +%F	YYYY-MM-DD	Date; shown in YYYY-MM-DD	2018-01-19
# date +%H	Hour	Hour in 24-hour clock format	18
# date +%I	Hour	Hour in 12-hour clock format	10
# date +%j	Day	Day of year (001..366)	152
# date +%m	Month	Number of month (01..12) (01 is January)	05
# date +%M	Minutes	Minutes (00..59)	52
# date +%S	Seconds	Seconds (00..59)	18
# date +%N	Nanoseconds	Nanoseconds (000000000..999999999)	300231695
# date +%T	HH:MM:SS	Time as HH:MM:SS (Hours in 24 Format)	18:55:42
# date +%u	Day of Week	Day of week (1..7); 1 is Monday	7
# date +%U	Week	Displays week number of year, with Sunday as first day of week (00..53)	23
# date +%Y	Year	Displays full year i.e. YYYY	2018
# date +%Z	 Timezone	Time zone abbreviation (Ex: IST, GMT)	IST