The history of traps in RPGs is the history of traps in D&D; and the history of traps in D&D is the history of the Rogue class in D&D, formerly called the Thief.
The article describes the introduction of the Thief class and its effects on the evolution and ecology of traps in D&D through the “old school” period of 1974-1999; then explains the changes and shake-ups introduced by 3rd edition mechanics (2000-present, including Pathfinder). Along the way, the article gives GM tips gleaned from the history of traps.
By way of conclusion, the article explains the major change 5th edition made to traps, and how it impacts how you should be running them.
Because this is a longer and more complicated article than usual for this site, I laid it out in a PDF for easy reading.