The cloud simply means software and storage that run on someone else's computers, in secure data centres, and which you reach through the internet. Rather than buying and maintaining a server in a cupboard, you use capacity provided by a specialist company and typically pay for what you use.
For a business this usually means access from any site or device, automatic maintenance and easier recovery if something fails. It does not mean the data is unprotected or unlocated: it is held in real facilities, often in a chosen country. It is worth knowing where your data sits and who is responsible for protecting it.