Why It Is Offensive To Give/Receive With Your Left Hand?

I bought recharge card from an elderly woman today along the street on my way back from an errand. While giving me my change, she passed it with her left hand cos right was occupied but she quickly apologised that I shouldn't be offended.

My question is; why is it offensive to give or receive with the left hand
I know it's a common thing in many cultures but I don't know the reason why.



Plz share your thoughts.