Add: some readme documentation on snippets (#97)

README.md

@@ -122,3 +122,23 @@ It also means being open to feedback yourself, and being willing to learn from o
 
 It should be noted that this also means that sometimes pull requests will be rejected.
 A rejection does not mean that your contribution is not valued, but rather that it is not a good fit for the project at this point in time.
+
+# Conventions
+
+## Snippets
+
+There are various places where we insert code snippets into the documentation to better visualize what's going on.
+
+Snippets are placed in the `snippets` folder, grouped in subfolders by topic. Each snippet is a separate file per language (based off of its extension), with a central (autogenerated) `.md` file that includes the snippets for each language. If you want to add a new language to a snippet, create the new file, and the build pipeline will automatically include it in the final documentation.
+
+If you are adding the first snippet for a new language, it will need to be defined in `scripts/generate-snippets.py`, so that the build pipeline knows to include the file extension when searching for snippets, and what langauge to use for syntax highlighting.
+
+When adding new snippets, write it in any supported/configured language, and include it as follows:
+
+```markdown
+--8<-- "snippets/path/to-filename.md"
+```
+
+Note the .md extension to use the autogenerated file, and the `--8<--` to indicate that this is a snippet include.
+
+If a certain topic contains a lot of snippets, it might also be time to create a guide page for that topic, so that newer users can use that guide as a starting point.