Original: Throughout the series' history, there have been several kinds of Mushroom power-ups, including a 1-Up Mushroom, which gives Mario an extra life; Poison Mushroom, which causes Mario to either shrink or die; Mega Mushroom, which causes Mario to grow very large; and Mini Mushroom, which causes Mario to shrink.
Simplified: New Super Mario Bros. introduced other types of Mushroom power-ups, such as the "Mega Mushroom", which causes Mario to grow to screen-filling proportions and the Mini Mushroom that makes him shrink to a very small size.