CloudDrive is a free client software for Adobe Acrobat Online Storage Service, which offers 5GB free online storage for each account. So, when you use CloudDrive, all your files are stored in Adobe Acrobat Online Storage Service.
Why we need such a client software? We already have Google Docs, Microsoft SkyDrive, Acrobat Document Service and... Cann't I use them directly?
Ok, Adobe Acrobat Online Storage Service, like most other cloud storage solutions, such as Google Docs, Microsoft Skydrive, only offers you to upload/download files through their websites. Thinking about uploading a large file or folder, which probably takes hours to finish, in the whole process, you cannot close the webpages or turn off your computer! There is no way to do the lengthy job silently in backgourd.
This is not too bad? Ok, Here is the really bad thing: All these services do not allow you to upload a folder! Want to upload a folder with hundreds of files/subfolders in it? Forget it! It would be a nightmare!
CloudDrive comes to rescue! Upload/Download any files/folders with just a drag&drop!