Which "cloud?" There is a Google cloud, an Apple cloud, a Microsoft cloud, an Amazon cloud, an Adobe cloud, and on and on *ad nauseum*. People talk about "The Cloud" like it's some kind of magic thing up in the sky but it really is nothing more than a fancy name for storing your data on some internet server somewhere, probably in some huge data center. Whoever runs the "cloud" you are using can look through your files all they want to, there is no guarantee of privacy: check the TOS. Yes, some companies definitely scan their clouds looking for "illegal" content. Best thing to do might be to set up your own file server at home and have a "personal cloud." I use a self-secured Linux computer with RAID, and access it remotely using SSH/SFTP. --but also, you can purchase consumerized NAS devices that do this sort of thing without a lot of know-how. (Beware of the OS and backdoor support systems that come installed on these, however.)