My favorite: "dd" the "copy and convert" command, but "cc" was already taken by the C compiler.

I thought it came from JCL's DD (Data Definition) statement. Even the parameter syntax is somewhat reminiscent of JCL's DD, while being completely alien to normal Unix commands.

sverige

I still pause to remember that I have to type 'if=' and 'of=' and 'bs=' instead of just remembering the order of arguments.

dmartinez

`tldr`[0] can be helpful for quick references like this. I never worry about commands like `ssh` anymore because of this. This is the output for `dd`:

$ tldr dd

Convert and copy a file.

- Make a bootable usb drive from an isohybrid file (such like archlinux-xxx .iso):

    dd if=file.iso of=/dev/usb_drive

- Clone a drive to another drive with 4MB block and ignore error:

    dd if=/dev/source_drive of=/dev/dest_drive bs=4m conv=noerror

- Generate a file of 100 random bytes by using kernel random driver:

    dd if=/dev/urandom of=random_file bs=100 count=1

- Benchmark the write performance of a disk:

    dd if=/dev/zero of=file_1GB bs=1024 count=1000000

[0]: https://github.com/tldr-pages/tldr