The Roman letters were categorized according to ascender, descender, serifs, counter, loop etc. But Devanagari letters till then had not been subjected to such a graphical analysis. One of the first attempts towards a graphical classification was done by S.V. Bhagwat (1961) in his thesis. Bhagwat’s main insights on the graphical structure of Devanagari are enlightening.
Bhagwat groups on the basis of graphical similarity and then he goes on to define the guide lines for the same graphical elements of letters. The top most lines are the Rafar line, followed by the Matra line and Head line. The Head line is also referred to as the Shirorekha. After the Shirorekha, the upper mean line and lower mean line are indicated. The upper mean line denotes the point from which the actual letter starts and the lower mean line in marked where the distinguishing characteristics of the letters come to an end. These lines are followed by the Base line, which is where the complete letter ends and the lower matras begin. The lower most line is the Rukar line where the lowest portion of the Rukar ends. His new contribution to vocabulary of graphic elements of Devanagari is the term Loop, which is used to describe top of the letter.
Bapurao Naik also attempted a graphical grouping titled Graphical classification of Devanagari Varnas of letters. Naik graphically organizes Devanagari letters into five groups based on the position of the Kana or Verti-bar.
Creating a vocabulary for Devanagari was done by Mukund Gokhale, it was first published in 1975-76. Gokhale uses the body paradigm to describe the various portions of the letters. The lines defined by him are: Urdhavarekha, Shirorekha, Skandhrekha, Nabhirekha, Janurekha, Padrekha, and Talrekha. Regarding the proportion of the letters, Gokhale uses the stroke thickness (thickness of pen stroke) as a base unit. Four strokes for upper matras, eight strokes for main character and four strokes for bottom matras are necessary. A total of sixteen units of strokes can be considered as primary height of the letter. Bapurao Naik also specify this units of heights, six strokes for upper matra, twelth strokes for main character and again six unit for bottom matras in total twenty four units.
The description of the various parts of Devanagari letters by Gokhale is called Cartographic description of Devanagari in his article.