dd Command - Convert and Copy Files

dd is a command-line utility for Unix and Unix-like operating systems whose primary purpose is to convert and copy files. It is commonly used for backing up and restoring entire drives or partitions, creating bootable USBs, and more.

Syntax

dd if=[input_file] of=[output_file] [options]

Examples

dd if=/dev/sda of=/dev/sdb bs=4M status=progress

dd if=/dev/cdrom of=cdrom.iso

Notes

• Be extremely careful with input and output files to avoid data loss.
• Requires root privileges for device-level operations.
• Use status=progress to monitor progress in modern dd versions.