We have approached how computers display bitmaps on a screen, or store this information on a file. We have seen ASCII and this covers for text, which is already a huge part of what we need to communicate. But Latin alphabet is short of advanced applications. It's good enough for the news, maybe for literature, but how about science? Let's have a look again at one of the oldest equations which humanity has dealt with:
$$x_{1\atop 2}=-{b\pm\sqrt{b^2-4ac}\over 2a}$$
This is the modern notation. It has not always been so neat and structured, being overlayed all over the place with parts of it which extend over others, etc., but it has always required going beyond mere text (and that includes numbers). In particular, in Science, we use a lot Greek letters.