Related Clues:

• "The Da Vinci ___"
• Bed intruders?
• Try to make undecipherable
• Secure, as information
• Make harder to read
• Do programming work
• Zip --
• Program listing?
• Write software
• Software basis
• Bar closing?
• Turn message into secret symbols
• Encryption or set of rules
• Cryptogram or set of standards
• Computer instructions