For example a deal may don the title of '10 Free Spins No Deposit' while another sign up bonus may holler '£/$/€ 10 free casino bonus'. They can differ from one promotion to the next and some may be titles are no deposit free spins offers while others may serve up bonus cash to play slots or even bonus spins.
So you're asking, 'what is a no deposit slot bonus? and what's the fuss about!?' An online slots no deposit bonus is a promo deal offered to a new customer (casino fan) when they open up a new player account at a new casino that lets them play slots for free.