What is the difference between Roman Catholicism, Maronite Catholicism and Melkite Greek Catholicism?

Mostly language and practice. All doctrine is the same.

Actually there are over 20 different Catholic Churches that make up the worldwide Catholic Church.

In addition to the Latin Rite (Roman) Catholic Church, the Eastern Rite Catholic Churches are in full communion with the Pope, and are part of the same worldwide Catholic Church.

Eastern Rite Catholic Churches include:

Alexandrian liturgical tradition

• Coptic Catholic Church

• Ethiopic Catholic Church

Antiochian (Antiochene or West-Syrian) liturgical tradition

• Maronite Church http://www.bkerkelb.org/

• Syrian Catholic Church

• Syro-Malankara Catholic Church http://www.syromalankara.org/

Armenian liturgical tradition:

• Armenian Catholic Church http://www.armeniancatholic.org/

Chaldean or East Syrian liturgical tradition:

• Chaldean Catholic Church

• Syro-Malabar Church http://www.smcim.org/

Byzantine (Constantinopolitan) liturgical tradition:

http://www.byzcath.org/index.php?option=com_conten...

• Albanian Byzantine Catholic Church

• Belarusian Greek Catholic Church

• Bulgarian Greek Catholic Church

• Byzantine Church of the Eparchy of Križevci

• Greek Byzantine Catholic Church

• Hungarian Greek Catholic Church

• Italo-Albanian Catholic Church

• Macedonian Greek Catholic Church

• Melkite Greek Catholic Church http://www.pgc-lb.org/english/index.shtml

• Romanian Church

• Russian Byzantine Catholic Church

• Ruthenian Catholic Church

• Slovak Greek Catholic Church

• Ukrainian Greek Catholic Church http://web.archive.org/web/20080210111559/http://w...

http://www.newadvent.org/cathen/13121a.htm

With love in Christ.

I believe it is differences in the liturgies. There are also Coptic Rite and Celtic Rite Catholics.

Their stupid names...