What runs on startup?

On El Capitan, how can I view what programs run on startup, and possibly disable some?

You cannot control much, but you can see what starts when YOU login by going to System Preferences/Users & Groups/ pick your login and look at Login Items. Anything on that list starts when you log in. IF there is something you don't want, click on it and then on the "-" at the bottom of the window. Clicking the check box just hides the application, doesn't remove it from the start up.

Most (if not all) of what starts at boot before you log in you need. Don't muck with it.

Jake, thank you. That is exactly what I wanted to know. I appreciate your time!

Matty see the little thumbs up on Jake's response. Click on it and leave feedback as he helped you.