date.txt

# Formatting dates. The format string begins with \e[38;5;201;1m+\e[0m
date +%Y-%m-%d   \e[36m# 2025-03-05\e[0m
# or shorter:
date +%F         \e[36m# 2025-03-05\e[0m
date +%b --> "Apr"

# Times
+%s        \e[36m# seconds since epoch ("unix timestamp")\e[0m
+%H:%M:%S  \e[36m# 14:42:58\e[0m
# or shorter:
+%T        \e[36m# 14:44:22\e[0m

# Input date:
--date/-d string
# where string can be all sorts of wacky shit, and also accepts +/-n day/month modifiers
# if the input is a timestamp, prefix a \e[38;5;208m@\e[0m
$ date -d \e[38;5;201;1m@\e[0m1749655073
Wed Jun 11 05:17:53 PM CEST 2025

# last date of the month: get the current 1st day of the month, add a month, subtract a day, print as date:
date -d $(date +%Y-%m-01)' +1 month -1 day' +%F   \e[36m# 2025-03-31\e[0m