What is Interco or International Code of Signal and its purpose & content?

Contents of Interco:

Chapter I: Signalling Instructions

Section 1: Explanation and General remarks
Section 2: Definitions
Section 3: Methods of Signalling
Section 4: General Instructions
Section 5: Flag Signalling
Section 6: Flashing Light Signalling
Section 7: Sound Signalling
Section 8: Radio  Telephony
Section 9: Morse Signalling By Hand Flags Or Arms
Section 10: Morse Symbols-Phonetic Tables- Procedure Signals

1. Single letter signals
2. Single letter signals with complements
3. Single Letter Signals between Icebreaker And   Assisted Vessels
4. Identification of medical transport in armed conflicts and permanent identification of rescue crafts.

To remember the contents in the first section make note of the following Sentence:

“Every Day Must Go For Fun, Somehow Request Mother Mary  Send Some Sweets Immediately”