What is the difference.

Your history book does not even give you the background on both? Do you think they are one and the same?

First, the Magna Carta was many years before the U.S. Constitution. In 1215, In England, this document was drawn up and the King was forced to sign it. When the founders of this country - the United States - came together, they drew from the Magna Carta and took these rights to represent all:

These rights included: The right of jury trial, protection of private property, limits on taxation, and some religious freedoms.

Note that these rights were intended to be enjoyed by the rich; it didn't apply to the people (in England). These rights above became a part of our Bill Of Rights and apply to all.

The Magna Carta was not the only resource used in drafting the U.S. Constitution.
Read through the following: Democracy and the Origins of the US Constitution (http://www.sullivan-county.com/bush/constitution.htm)

Now you can read through the online Magna Carta: The Magna Carta - The U.S. Constitution Online - USConstitution.net (http://www.usconstitution.net/magna.html)
More historical information on the Magna Carta: Magna Carta - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Magna_Carta)
The U.S. Constitution: United States Constitution - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/United_States_Constitution)