As developers we all spend a lot of time trawling through Stack Overflow looking for answers but what article do you keep going back to and why? It could be something very simple, a tutorial or a comprehensive guide to a specific topic.

For me it's A Visual Explanation Of SQL Joins by Jeff Atwood (coincidentally was the guy who created the Stack Exchange network of sites), whether it's helping out another dev or just jogging my memory i've come back to this article time and time again as it's such a simple and effective way of communicating a relatively hard idea to explain verbally.