You could do worse than to confuse the meanings of "code" and "cipher"—even cryptographers sometime use the terms as though they had the same meaning. There is, however, a definite distinction ...

In Part I, you broke a simple cipher. Now try creating a more complex cipher. Cut out the NOVA Decoder Ring and NOVA Cipher Code Ring and the window marked INDEX. You are now going to put this ...

The Code and Cipher Compilation Subsection established secure communications for 40-plus military attachés and hundreds of intelligence officers in the American Expeditionary Forces.