To clone a hard drive to another hard drive, launch backup or other disk-imaging software, and select the hard drive to clone and the hard drive to clone it to. When cloning is complete, you should have an exact duplicate of the original drive, including the operating system.
Unlike incremental backups, where only new files and changes to existing files are saved, cloning creates an exact copy of the files and directory structure on the original hard disk. While sometimes much slower than other backups, cloning a disk means that the copy on the second or new hard drive is ready to use immediately.
Although it can also preserve data errors and bad directories (especially when cloning a drive where the physical disk is damaged), cloning is also the most straightforward method of backup because it requires two working drives to complete the procedure. In addition, cloning is the bulkiest in terms of storage. However, clones can be updated fairly easily with syncing software. Using a combination of cloning and disk-imaging – where another copy of the clone is saved to a compressed file that is smaller and easier to store – gives you a double layer of data protection with both a working copy and archival copies for backup.