Q: Why Latex compiler seems to be bound to PostScript? I am considering the following facts about the latex compiler:


*

*It only takes PostScript (PS) or Encapsulated PostScript (EPS) files as image input;

*It produces only DVI files as output, which can be converted in PS file;

*It understand only T1 type fonts, which is a PostScript font format.


Why this compiler seems to be so strongly bound to PostScript? Is there a historical reason? And why the other more recent compilers (pdflatex, xeletax, lualatex) do not have this binding anymore?

A: Of the three bullet points only the middle one is correct. Classic TeX produces DVI output. As the name implies, DVI files are device independent and not tied to PostScript.
The DVI file just references fonts and images by name so is not tied to any particular format (for fonts you just need the font metrics)
What is true is that if you then process the dvi file with dvips then the image and font formats that can be handled depend on that driver. So your question is "why is dvips bound to PostScript" and the answer basically is that generating PostScript is what it is designed to do.
If you process the dvi file with dvipdfm(x) to produce PDF or dvisvg to produce svg, or dvilj to produce HP printer control language, the font formats and image types that can be handled would be quite different.
