Cloud backup differs from local backup in its storage location and accessibility. Cloud backup involves storing data on remote servers managed by third-party services, allowing users to access their information from anywhere with an internet connection. This method provides enhanced security, as cloud services often employ encryption and redundancy measures. In contrast, local backup stores data on physical devices like external hard drives, limiting access to specific locations and increasing the risk of data loss due to hardware failure. Cloud backup solutions generally offer more flexibility and convenience.