The Sanskrit syllables and letters are represented in the symbols scientifically based on the origin of the sound. For instance the letter Om in Sanskrit has been symbolized on the basis of the sound.  Om- split as aaa oooo mmm the sound of the syllable mmm comes from chakra near the navel and hence the dot above curve you see in the symbol represents that. Similarly for others. If you study Sanskrit language and see, the English language appears stupid. The Sanskrit used in Bhagavad Gita is kind of elementary for Sanskrit scholars. Lord Krishna made it so simple yet it is a open secret that dull brains doing sense enjoyment can't understand or recognize. This is why it is mentioned as confidential knowledge all though available for everyone.

This Sanskrit language has been primarily and widely used in the previous yugas as well.

Based on the teachings of HG. Ravindra Svarupa Das (RSD)