This is the introduction to a series of articles that will comparatively explore the slew of tabletop roleplaying games that have spawned from old school gaming movement. This is often known as the 'OSR' which means 'Old School Revival' or 'Old School Renaissance.' This article will be discussing some of the key design principles that tie these many varied games together.
These roleplaying games are ostensibly inspired by the original versions of D&D such as original D&D, the Basic & Expert line of D&D as well as AD&D. You can read more about those here.