@@ -128,3 +128,58 @@ This is especially helpful to generate *really lightweight* documents.::
128128 free versions of the proprietary fonts.
129129
130130 This also violates the *what-you-see-is-what-you-get * feature of Matplotlib.
131+
132+ Are we reinventing the wheel?
133+ -----------------------------
134+ Internally, a feasible response to the question of 'reinventing the
135+ wheel would be, well, Yes *and No *. The font-matching algorithm used
136+ by Matplotlib has been *inspired * by web browsers, more specifically,
137+ `CSS Specifications <http://www.w3.org/TR/1998/REC-CSS2-19980512/ >`_!
138+
139+ Currently, the simplest way (and the only way) to tell Matplotlib what fonts
140+ you want it to use for your document is via the **font.family ** rcParam,
141+ see :doc: `Customizing text properties </tutorials/text/text_props >`.
142+
143+ This is similar to how one tells a browser to use multiple font families
144+ (specified in their order of preference) for their HTML webpages. By using
145+ **font-family ** in their stylesheet, users can essentially trigger a very
146+ useful feature provided by browers, known as Font-Fallback. For example, the
147+ following snippet in an HTMl markup would:
148+
149+ .. code-block :: html
150+
151+ <style >
152+ someTag {
153+ font-family Arial , Helvetica , sans-serif ;
154+ }
155+ </style >
156+
157+ <!-- somewhere in the main body -->
158+ <someTag >
159+ some text
160+ </someTag >
161+
162+
163+ For every character/glyph in *"some text" *, the browser will iterate through
164+ the whole list of font-families, and check whether that character/glyph is
165+ available in that font-family. As soon as a font is found which has the
166+ required glyph(s), the browser moves on to the next character.
167+
168+ How does Matplotlib achieve this?
169+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
170+ Well, Matplotlib doesn't achieve this, *yet *. It was initially only designed to
171+ use a **single font ** throughout the document, i.e., no matter how many
172+ families you pass to **font.family ** rcParam, Matplotlib would use the very
173+ first font it's able to find on your system, and try to render all your
174+ characters/glyphs from that *and only that * font.
175+
176+ .. note ::
177+ This is, because the internal font matching was written/adapted
178+ from a very old `CSS1 spec <http://www.w3.org/TR/1998/REC-CSS2-19980512/ >`_,
179+ **written in 1998 **!
180+
181+ However, allowing multiple fonts for a single document (also enabling
182+ Font-Fallback) is one of the goals for 2021's Google Summer of Code project.
183+
184+ `Read more on Matplotblog <https://matplotlib.org/matplotblog/ >`_!
185+
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