Pre Linux, I used Windows.. (too many years in the wilderness :) ... however there was a ray of sunshine in amongst all the general virus/re-install flack.. and that was Notepad++, a text Editor I really like(d).   I'd probably still be using it, even now that I've shifted fully across to Linux(Ubuntu), but it doesn't behave 100% in 'wine'... (and its regex is stunted)...  There is one feature in Notepad++ which I sorely miss, and that is the ability to display different SIZE fonts within a single document (at the same time)... At some point, I started learning Hindi, and found that the Devanagari script really needs to be larger than the Latin script (used here)... Devanagari is by nature a taller script, with frills above, and below the main line, and has more detail.   Because of this I utilized Notepad++'s Syntax Highlighting to display my learning notes in a manner my eyes could handle...  Now my dilemma, is to find a Linux Text Editor which can (at least) do what Notepad++ can do  (ie. allow me to specify my own mix of font SIZES, and also to specify my own comment-delimiters)...   Now, the big ask... What I would really like is an editor which is Human-Language aware, or Font-Type aware, or Unicode-Codeblock aware...  so I don't have to fiddle and twiddle with syntax-highlighting, which is really not intended for what I want..  (PS... I don't want a word-processor)  In October, last year, I asked here about SciTe (Scintilla) specifically (Notepad++ is based on Scintilla), but as per one answer, it is too painful :) ...  A comment suggested that Emacs could do it, so if that means at the same time, then I'm interested, but I need some initial pointers on how to go about it...  Here is an example of the Notepad++ presentation..  
Text editor with font-size selection for specific human languages (ie. Unicode Block) eg Devanagari
editors;emacs;fonts;highlighting;unicode
Emacs has the ability to show fonts with different faces, colors, and sizes in the same buffer.  For instance, the following is produced by the AUCTeX major-mode, a useful mode for those who use LaTeX to create documents:The two search terms that will be helpful are font-locking and major mode. Essentially, to accomplish this in Emacs you would have to write your own major mode.  Unfortunately, this basically amounts to you having to fiddle and twiddle with syntax-highlighting, but on steroids.For your particular purpose, the most difficult part will be properly displaying the Devanagari script.  Everything else is relatively straight forward.  The best places to get started are the EmacsWiki and the Emacs Manual.  The following links might be useful:Emacs Manual:Major-ModesEmacsWiki: Mode TutoriaEmacsWiki: Derived ModeEmacsWiki: Generic ModeEmacsWiki: Hindi SupportSince you really only need your mode to provide font locking, I would take a look at making a Derived Mode (see the relevant link above).  Creating such a mode basically involves defining regular expressions that will match the various parts of the code you want highlighted in a certain way, and then assigning that either to one of the predefined font-lock faces or a custom face you would define.