Pope Francis has just released an Apostolic Exhortation called Evangelii Gaudium (The Joy of the Gospel). He also released an Encyclical Letter in the summer called Lumen Fidei (The Light of Faith). What is the difference between these two types of documents? Is once considered to be more important than the other?
Apostolic Exhortation is a type of communication from the Pope that is written to encourage people to undertake an implementation of particular set of recommendations listed in the document.
Encyclical Letter which is usually more important than Apostolic Exhortation is a letter that usually deals with a specific doctrine, where the doctrine is clarified, or explained in greater detail.
On the cover of Evangelii Gaudium it has the further description "Apostolic Exhortation on the Proclamation of the Gospel in today's world". Inside on the publishing page it says an "Encyclical Letter of Pope Francis Evangelii Gaudium". An exhortation is what it is FOR. An encyclical is what it IS.