One of the new features of the 4E rules was the implementation of formal roles. All Dungeons & Dragons classes now fit into one of four roles: controller, defender, leader, or striker. In brief, for those few readers who may not be familiar with these terms, a controller uses area of effect abilities to manipulate [...]

A 4E player character has a class “fueled” by a power source that fills a role. There are multiple builds within a class that provide a player with a template that optimizes their abilities for a certain playstyle. As more classes are added to fill holes in the role/power source matrix, and more builds are [...]

Advanced Dungeons & Dragons Second Edition (2E) grouped classes into three “superclass categories”: warrior, priest and mage. This categorization was dropped in Dungeons & Dragons Third Edition (3E), replaced with a distinction between arcane magic, divine magic and everyone else. D&D 4E merged these concepts in the form of class power sources. From the 4E [...]

I would have done it differently. The Player’s Handbook (PHB) for the 4th Edition (4E) of Dungeons and Dragons included eight classes from three power sources. All four of the new roles where covered, though some of the power sources lacked a class in one or more roles, and one power source had two classes [...]