Decoding the Dabbawalla Iconography
The diagram above depicts a sample set of icons that are marked on a 'dabba'. These icons help to identify the pickup and delivery points and also contain codes that help the different groups of 'dabbawallas' to identify their set of 'dabbas' at each leg of the journey.

These icons have been evolved because of the need of berivity. Also many of the 'dabbawallas' are illiterate and cannot follow written names and addresses, but the icon system - of symbols and colour codes - works for all. Since each set of 'dabbawallas' transport the 'dabbas' for only a part of the journey, these icons also help the sorting of the 'dabbas' at each juncture before they make the onward journey.
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THE EVOLUTION OF ICON DESIGNS:
      
The 'dabba' icons reflect the influence of traditional design motifs (see above, left). The shapes of the icons also derive from the geographical forms and landmarks (see above, centre and right)
Represented below are the icons used by the 'dabbawallas' for the different train stations along the western railway line. The names of the stations are written alongside; the main stations are in red.