The major change of the Meiji Restoration was that Japan modernized in major ways. It did this because the Perry expedition had shown it just how far behind the West it was and how vulnerable it was to Western power.
Because of this, Japan competely remade itself. The old feudal system of samurai and daimyo was dismantled. In its place was put a government that was officially headed by the emperor but which had a pretty western-style constitution. Along with that, the economy was modernized. The government pushed hard to make Japan into an industrial country as opposed to the old-fashioned agrarian country that it had previously been.