Please explain who I owe my student loans to: I logged into my sallie mae account?

and see that there are two columns, one for stafford loans and the other one is for Direct loans -sub. I need to ask for a deferrment but I noticed that whatever tab i click on it gived two options: "federal and private loans" and "department of education loans". SO my question is this: didnt there ised to be a separate website to service dept of educ loans --something like direct.gov or something? Does Sallie Mae take the payment for all student loan payback now? i dont totally understand who im actually paying back? thanks for any simplification