diff --git a/README.md b/README.md
index 0c1237e..5eda2ef 100644
--- a/README.md
+++ b/README.md
@@ -13,3 +13,29 @@ URL generation:
 * `implicitGrant`
 * `loginCode`
 * `resourceOwnerPassword`
+
+URI vs URL
+----------
+
+See <https://danielmiessler.com/study/url-uri/#gs.=MngfAk>
+
+Since we do not require the `protocol` to be specified, it is a URI
+
+However, we do have a problem of disambiguation since a URI may look like a `path`:
+
+1. https://example.com/api/org.oauth3.provider
+2. example.com/api/org.oauth.provider/ (not unique)
+3. /api/org.oauth3.provider
+4. api/org.oauth3.provider (not unique)
+
+Therefore anywhere a URI or a Path could be used, the URI must be a URL.
+We eliminate #2.
+
+As a general rule I don't like rules that sometimes apply and sometimes don't,
+so I may need to rethink this. However, there are cases where including the protocol
+can be very ugly and confusing and we definitely need to allow relative paths.
+
+A potential work-around would be to assume all paths are relative (elimitate #4 instead)
+and have the path always key off of the base URL - if oauth3 directives are to be found at
+https://example.com/username/.well-known/oauth3/directives.json then /api/whatever would refer
+to https://example.com/username/api/whatever.