some README intro words

README.md

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 cleanroom TUI library for modern terminal emulators. definitely not curses.
 
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+
+* What it is: a library facilitating complex TUIs on modern terminal
+    emulators, supporting vivid colors and wide characters to the
+    maximum degree possible. Many tasks delegated to Curses can be
+    achieved using notcurses (and vice versa).
+
+* What it is not: a source-compatible X/Open Curses implementation, nor a
+    replacement for NCURSES on existing systems, nor a widely-ported and -tested
+    bedrock of Open Source, nor a battle-proven, veteran library.
+
+notcurses abandons the X/Open Curses API bundled as part of the Single UNIX
+Specification, as the latter seems not capable of making use of terminal
+functionality such as unindexed 24-bit color ("DirectColor", not to be confused
+with 8-bit indexed 24-bit color, aka "TrueColor"). For some necessary
+background, consult Thomas E. Dickey's superb and authoritative
+[NCURSES FAQ](https://invisible-island.net/ncurses/ncurses.faq.html#xterm_16MegaColors).
+As such, it is not a drop-in Curses replacement. notcurses furthermore makes
+use of the Terminfo library shipped with NCURSES. It is almost certainly less
+portable, and definitely tested on less hardware.
+
+notcurses opens up advanced functionality for the interactive user on
+workstations, phones, laptops, and tablets, at the expense of e.g.
+industrial and retail terminals (or even the Linux virtual console,
+which offers only 8+8 colors and limited glyphs).
+
+Why use this non-standard library?
+
+* A svelter design than that codified in X/Open. All exported identifiers
+    are prefixed with `notcurses_` to avoid namespace pollution. Fewer
+    identifiers overall. All APIs natively suport wide characters and
+    24-bit RGB color.
+
+* Visual features not directly available via NCURSES, including images,
+    fonts, and video.
+
+On the other hand, if you're targeting industrial or critical applications,
+or wish to benefit from the time-tested reliability and portability of Curses,
+you should by all means use that fine library.