The changes have been in the works for years now. The new and revised Roman Missal is based on a literal translation of original prayers in Latin.
The current liturgy, has been in place for 41 years, but the wording is based more on the sentiments of the original prayer, and not exactly on a precise translation.
The changes will also be heard in some of the common chants sung during Mass.
On November 27th, which is the first Sunday of Advent, the changes will begin in English speaking regions like the United States, U.K, Africa and Australia.