Systems

• The Major System

  Consonant sounds map to digits 0–9. Vowels are free, so encoded numbers turn into pronounceable words.

• T9 phone keypad

  Letters mapped to digits 2–9 on legacy mobile phones. Words can be entered as their numeric sequence.

• Leet (1337-speak)

  Numbers and symbols substituted for similar-looking letters. Used since the early 1980s BBS scene.

• Cultural references

  Numbers that carry meaning beyond arithmetic: codes, addresses, agent IDs, recurring motifs.