A multitude of different experimental systems were developed to recognize handwritten letters and gestures like Tom Ellis' flowchart based Graphic Input Language (GRAIL) method.
Tom Ellis, an author of many RAND corporation reports, stated that this GRAIL system was what allowed the natural and real-time recognition of text and symbols written on the flowchart.
The tablet connects to the input channel of a general-purpose computer and to an oscilloscope display which controls the multiplexes of the pen position information.
By the time of the tablet's production, printed-circuit technology had advanced to allow a grid of copper strips on a bi-axially oriented polyethylene terephthalate (boPET) surface to yield a resolution of 0.01".
[3] A program was written in IBM 360 Assembler Language to allow an online computer user to write data and directives on the RAND Tablet.
Using point-by-point pen location, the scheme could immediately recognize and display 53 letters, numbers, and symbols in multiple printing styles as long as they adhered to coding conventions.
The tablet was able to pick up and identify multiple stroke symbols by analyzing the sequence of direction, end-point locations, and was even able to use contextual clues when necessary.
The tablet proved to be a straightforward, convenient, and easy means to position boxes, lines, arrows, text, and other annotations over the display map.