I just downloaded an installer of Jahshaka video editor and to my surprise its a 2kb shell script file. I have no clue on how to install it because I'm a little new to Linux.

What distro are you using?
From where did you get this shell script?
What is the name of the shell script?

I'm using Xubuntuu(for now)
I got the shell script from sourceforge as an install file.
Its called Jahshaka-dapper-x86.sh

Here's the script if that is on any help.

#!/usr/bin/env sh

function dapper_register( ) {
[ "`grep repo.jahshaka.org/ubuntu/dapper /etc/apt/sources.list`" = "" ] &&
echo deb http://repo.jahshaka.org/ubuntu/dapper/ binary-i386/ >> /etc/apt/sources.list
apt-get --quiet update 2>&1 > /dev/null
return $?
}

function dapper_simulate( ) {http://linuxcommand.org/writing_shell_scripts.php
apt-get --simulate install $* 2>&1
return $?
}

function dapper_install( ) {
apt-get --force-yes --yes install $*
return $?
}

function change_user( ) {
zenity --question --text "Welcome to the Jahshaka Ubuntu Installer.\n\nShould you wish to continue, I will need your password."
[ $? = 0 ] && packages=`chmod +x $1 && gksudo $1 install`
for i in $packages
do
(
echo [Desktop Entry]
echo Type=Application
echo Name=$i
echo TryExec=$i
echo Exec=$i
) > $HOME/Desktop/$i.desktop
done
}
http://linuxcommand.org/writing_shell_scripts.php
function install( ) {
info=`$register` && [ $? != 0 ] && zenity --error --text "$info" && exit

packages=`zenity --list --checklist --separator=" " --column "Download" --column "Package" $available`
[ "$packages" = "" ] && zenity --error --text "No packages selected." && exit

info=`$simulate $packages`
if [ $? = 0 ]
then
zenity --question --title "Jahshaka" --text "$info"
[ $? = 0 ] && ( $installs $packages | zenity --progress --pulsate ) &&
packages=`echo $packages | sed 's/openlibraries-media//'` &&
[ "$packages" != "" ] &&
zenity --question --text="Installation complete.\n\nDo you want me to create desktop icons for those applications?" &&
echo $packages
else
zenity --error --text "$info"
fi
}

if [ "$1" != "install" ]
then
( [ -f "/etc/issue" ] && uname -m | grep "i.86" && cat /etc/issue | grep "6\.06" ) > /dev/null
if [ $? == 0 ]
then change_user $0
else zenity --error --text "This script only applies to Ubuntu 6.06 x86 32 bit platforms."
fi
else
export available="TRUE jahshaka TRUE jahplayer TRUE jplayer FALSE openlibraries-media"
export register="dapper_register"
export simulate="dapper_simulate"
export installs="dapper_install"
install
fi

Open a terminal window and type: bash ./jahshaka-dapper-x86.sh

Well it didnt work because I dont have Ubuntu 6.06. But thanks for the help now I know how to install from shell scripts!