1. An optically readable record for storing encoded information; said record comprising a recording medium; a self-clocking data code for encoding said information; said data code being composed of glyphs that are written in a two dimensional code field on said recording medium on centers that are spatially distributed in nominal accordance with a predetermined spatial formatting rule; said glyphs being defined by respective symbols that are selected from a finite set of optically discriminable symbols to encode said information; and at least one additional glyph pattern that is written on said recording medium in nominal accordance with said spatial formatting rule, said additional code pattern providing physical addressing information for random access from any given location within said glyph pattern to any other given location within the same glyph pattern or another glyph pattern on the same or a differnt recording medium.