A guide to man-machine interface

USER-FRIENDLY
C:\ DUR
Command not found. Try retyping

USER-HELPFUL
C:\ DUR
I don't understand DUR. Do you mean DIR ?

USER-UNFRIENDLY
C:\ DUR
C:\ DUR
C:\ DUR
C:\ DUR

USER-HOSTILE
C:\ DUR
Ha! A mistake! I'm sure you meant to say FORMAT, so that's what I'll do.

USER-INDIFFERENT
C:\ DUR
DUR?

USER-PATRONIZING
C:\ DUR
Now, that's not quite right is it? Let's try again; this time, use the manual that the nice salesperson gave you when you bought me.

USER-OBSEQUIOUS
C:\ DUR
I'm so very, very sorry but I don't understand that. I'm sure it was my fault, but if you would please try again I'll do my best.

USER-SARCASTIC
C:\ DUR
Well, Look who's made a mistake then. Very unusual, I don't think.

USER-INSULTING
C:\ DUR
F*ck off
C:\ DIR
F*ck off

USER-SMUG
C:\ DUR
No
C:\ DOR
Nope
C:\ HELP
No
C:\ PLEASE
Not unless you give me a 300Mb hard disk to live on.
C:\ B*ST*RD
Abuse will get you nowhere

USER-ANALYTICAL
C:\ DUR
What makes you say that?
C:\ A TYPING MISTAKE
How long have you been making these mistakes?
C:\ BANANAS
Do you like bananas?
C:\ I LOVE THEM
Why do you bring up the subject of love?
...etc

USER-McDONALD
May I help you please?
C:\ DUR
I'm sorry but that command is not available at this time. Have a nice day.
C:\ DIR
Will that be an MS-DOS directory?
C:\ YES
To read here, or for printout to take away?
C:\ HERE
Thank you. Have a nice day.

USER-MEGALOMANIAC
C:\ DUR
Don't bother me with trivial requests. I'm busy.

Real users find the one combination of bizarre input values that shuts down the system for days.

Real users never know what they want, but they always know when your program doesn't deliver it.

Real users never use the Help key.

Real users never stop asking new options.

Real users never know what to do with new options.