The book of James was authored by the brother of Jesus. This is James who was leader of the Jerusalem council when he wrote the book. The nature of the book suggests it was addressed to the very early church, primarily Jewish Christians who knew James as an authoritative church leader. This would place the writing possibly as early as before a.d. 50, competing only with Galatians as probably the oldest book in the New Testament.
Dealing with the trials of being Christian, their role in discipline and our need for wisdom and thankfulness, James speaks of faith and deeds, worldliness and patience, and prayer for the afflicted. If you're dealing with temptations, addictions and lifestyle issues, the book of James is a must read.