What are the MTG Morph rules and how do they impact gameplay?

In Magic: The Gathering, Morph is a mechanic where you can play a creature face down as a 2/2 colorless creature for 3 mana. You can then pay its Morph cost to flip it face up, revealing its true identity. This adds an element of surprise and strategy to gameplay, as your opponent won't know what creature you have until you choose to reveal it.