dd
Unix-like operating system command
dd is a command-line utility for Unix, Plan 9, Inferno, and Unix-like operating systems and beyond, the primary purpose of which is to convert and copy files. Wikipedia
Example: dd if=floppy34.fs of=/dev/rfd0c bs=32k
Syntax: dd if=FILE of=FILE ibs=N obs=N bs=N count=N skip=N seek=N conv=notrunc|noerror|sync|fsync
Default block size: 512 bytes
Developer(s): Various open-source and commercial developers
Initial release: June 1974; 49 years ago
License: coreutils: GPLv3+; Plan 9: MIT License