Seamen need to keep a copy of this book onboard. There is a code in this book which allows the free download of an app. The app has additional graphic information and links to useful information. The International Code of Signals contains descriptions of signals and the various methods used to transmit them. The Code is intended to cater primarily to situations related to safety when language difficulties arise CHAPTER 1.-SIGNALING INSTRUCTIONS CHAPTER 2.- GENERAL SIGNAL CODE CHAPTER 3.-MEDICAL SIGNAL CODE CHAPTER 4.-DISTRESS AND LIFESAVING SIGNALS AND RADIOTELEPHONE PROCEDURES CHAPTER 1 SIGNALING INSTRUCTIONS SECTION 1: EXPLANATION AND GENERAL REMARKS SECTION 2: DEFINITIONS SECTION 3: METHODS OF SIGNALING SECTION 4: GENERAL INSTRUCTIONS SECTION 5: FLAG SIGNALING SECTION 6: FLASHING LIGHT SIGNALING SECTION 7: SOUND SIGNALING SECTION 8: RADIOTELEPHONY SECTION 9: SIGNALING BY HAND FLAGS OR ARMS MORSE SIGNALING BY HAND FLAGS OR ARMS SECTION 10: MORSE SYMBOLS-PHONETIC TABLES-PROCEDURE SIGNALS MORSE SYMBOLS PROCEDURE SIGNALS SINGLE LETTER SIGNALS SINGLE LETTER SIGNALS WITH COMPLEMENTS SINGLE LETTER SIGNALS BETWEEN ICEBREAKER AND ASSISTED VESSELS