dd

dd is a GNU coreutil tool for bytewise file copies. It's a lot like cat or cp but with powerful conversion options for the copy.

Flags

Flag	Description	Suggested value
bs	Block size, dd will read and write at this rate.	4M is safe for live installs
of	Output file path, redirects from stdout	Usually /dev/sdX
conv	Convert bytes in some way, specified from a list of options	Generally left blank
oflag	Output in a different way, specified from a list of options	direct if writing to device