cloud mining is an awesome way to mine Bitcoin (or any other crypto) without you to invest in expensive hardware or paying for any electricity costs.
A lot of cloud mining sites, however, are only made to get your hard-earned money into their pockets. They are nothing more than scam-sites, with a lot of promises, but when you claim your money you won't ever see it back!
Cooin.io instead, is one site you can trust. For the most, because they don't force you to invest in them, they even give you 20$ to try them out, you'll be able to withdraw your money once you reach the withdrawal amount (which is 25$). Also, all contact details (address and so) are shown on the site, which is something you won't find easily on scam-sites.