Hey guys . As the thitle says , then i just want to know what is this actually and how to learn that .
Thanks !
thitle, yes?

Flanger is a sort of effect which adds a cool sound to your playing. It is usually obtained through a stompbox or in-amp effects. As far as learning it, you can move your fingers over the strings lightly while picking rather fast to achieve a same sort of sound, nothing beats the real thing though.