How to call another Content from the same page with onclick Like sign up or Log in

For Example i onclick on Sign up or Log in button then on that page all other contends will be hidden in div only, then input register or Log in page comes in. Again every time i want go back to log in i click the link then register or login page will be hiddeden then enter image description hereCould Any body Tell me How To do that

AFTER ONCLICK EITHER OF THEM

THIS SHOULD APPEAR WITH THE LINK I EITHER GO BACK LOGIN OR JUST COMPLETE THE INPUT