something that brings pleasure but would not cause damage if one lacked it.
something that is necessary for physical or emotional survival.
not having access to getting all of your basic needs met. This can mean that you sacrifice physical needs to meet emotional ones or vice versa, or that you don't even have that option.
having so many resources that you can easily meet all your needs each month and have some left over, and are also able to manage unexpected expenses without sacrificing any needs.