They freely published their research on how to make codes.

"That demonstrates to me that there is theory about making codes that is not known to the outside world," he said.

This is where Leo Marks toiled to make unbreakable codes.

He was also an adept cryptographer who loved puzzles as well as making and breaking codes.

They think it is fun to make codes, and fun to break codes.

Their job is to break other people's codes, and to make codes that the United States government can use, which are hard to break.

Their goal is to protect the US people, by making codes and breaking codes.

Old men spend hours and hours making Omani codes.

They are used by governments to make and break codes, predict weather and target nuclear weapons.

What makes codes like this so jarring isn't that they are routinely enforced.