So been reading the grinders manual and came across the term RE with a corresponding chart that outlines our RE percentage to make a call

for example or RE% for a pot size bet is 33% or for a half pot bet it is 25%

But when using a BE% chart half pot is 33% and pot is 50%

what's the meaning of this and when should I use each chart I am confused i have always used the BE% based on pot odds to make decisions have I been doing it wrong