echo -e "\e[38;5;82mHello \e[38;5;198mWorld"

for i in {16..21} {21..16} ; do echo -en "\e[38;5;${i}m#\e[0m" ; done ; echo

echo -e "\e[40;38;5;82m Hello \e[30;48;5;82m World \e[0m"

for i in {16..21} {21..16} ; do echo -en "\e[48;5;${i}m \e[0m" ; done ; echo

#!/bin/bash
 
# This program is free software. It comes without any warranty, to
# the extent permitted by applicable law. You can redistribute it
# and/or modify it under the terms of the Do What The Fuck You Want
# To Public License, Version 2, as published by Sam Hocevar. See
# http://sam.zoy.org/wtfpl/COPYING for more details.
 
#Background
for clbg in {40..47} {100..107} 49 ; do
	#Foreground
	for clfg in {30..37} {90..97} 39 ; do
		#Formatting
		for attr in 0 1 2 4 5 7 ; do
			#Print the result
			echo -en "\e[${attr};${clbg};${clfg}m ^[${attr};${clbg};${clfg}m \e[0m"
		done
		echo #Newline
	done
done 
exit 0

#!/bin/bash
 
# This program is free software. It comes without any warranty, to
# the extent permitted by applicable law. You can redistribute it
# and/or modify it under the terms of the Do What The Fuck You Want
# To Public License, Version 2, as published by Sam Hocevar. See
# http://sam.zoy.org/wtfpl/COPYING for more details.
 
for fgbg in 38 48 ; do # Foreground / Background
    for color in {0..255} ; do # Colors
        # Display the color
        printf "\e[${fgbg};5;%sm  %3s  \e[0m" $color $color
        # Display 6 colors per lines
        if [ $((($color + 1) % 6)) == 4 ] ; then
            echo # New line
        fi
    done
    echo # New line
done
 
exit 0