Add to ORKGBachelor thesis deals with data backup and thereby preventing their loss. It defines the terms used and describes the principles of storing the data on the backup device for understanding and determination of backup operations. The theoretical part describes the possibilities of data storage by using backup software. In practical part cloud storages are tested in terms of speed of downloading and uploading for large, medium and small files. Testing is carried out by a Web browser and synchronization software of the cloud storage. For testing are selected services from large companies with the possibility of free testing. The practical part contains financial comparisons for the space of 1 TB, 10 TB and more. In the end is evaluation of bene...