You can create a current backup image of your Windows 8 computer to any USB flash drive or an external hard drive. A backup image stores information about the data, programs and other applications. In case of any issues in future this hard drive can be used to restore the backup you created.
To create backup image of Windows 8 computer to an external hard drive, follow the below given steps:
1) Press Windows key + X.
2) Click on Command Prompt(Admin)
3) In the command prompt, type: wbadmin start backup -allCritical -backupTarget:g:
Here, g: was the location of my external hard drive. You can change it as per your requirements.
4) Hit Enter.
5) You will get a confirmation message: Do you want to start the backup operation?
6) Type: Y and hit enter.
Backup will now start and it will take some time to finish.