Shell script show the ability of display foreground and background color. From http://misc.flogisoft.com/bash/tip_colors_and_formatting

bash_color.sh

# 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.
 
# Colors and formatting (16 colors)
#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
 
# 256 colors
for fgbg in 38 48 ; do #Foreground/Background
  for color in {0..256} ; do #Colors
		#Display the color
		echo -en "\e[${fgbg};5;${color}m ${color}\t\e[0m"
		#Display 10 colors per lines
		if [ $((($color + 1) % 10)) == 0 ] ; then
			echo #New line
		fi
	done
	echo #New line
done