#!/bin/bash  

clear
echo -e "Hello World"
echo -e "\e[1mHello World"    # bold effect
echo -e "\e[5mBlink"           # blink effect
echo -e "\e[0mHello World"      # back to normal
echo -e "\e[31mHello World"     # Red color
echo -e "\e[32mHello World"     # Green color
echo -e "\e[0m"                 # back to normal