1% and 2% Rule

[Shanel Wiggins]

Throughout my reading and education on deal analysis' for rental properties, including listening to @Brandon Turner on webinars, I learned to use the 1% or 2% rule just to sort out deals that may be worth the time looking more into. I know not to rely on this rule (or any rule to be exact), but I am confused on the difference of the two. Which one is best to use over the other?