For me PERSONALLY, weed can help me go to sleep or keep me awake. It depends on what I'm smoking. I tend to start the day with either a sativa or a predominantly sativa strain. I work my way to where I want to be and relax at home. When I'm ready for bed, a predominantly indica strain will allow me to sleep through the night. I usually have 3-4 strains to choose from. (More if I go to the dispensary)