What is the difference between rough er and smooth er? what is the er doing that is different in this case

The smooth endoplasmic reticulum is where the lipid and steroid synthesis occur also. Drug detoxification also occurs here. It's a bit innapropriate but how I remember it was LSD ( lipid and steroid we make drugs we do not take)

The rough endoplasmic reticulum are like airports, they bind proteins into little vessels and prepare them for transport to the Golgi apparatus