A professional who analyzes secret coding systems and decodes messages for military, political, or law enforcement agencies or organizations. Responsibilities include:

• Examines secret messages for characteristics that reveal coding system employed in message.
• Analyzes message, using formulas, code books, chemicals, mechanical devices, computers, and knowledge of commonly used coding keys.
• Decodes entire message and consults books, magazines, government publications, and police files to obtain corroborative evidence.
• May develop codes or new coding methods.