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+# Glossary
+
+<!-- TODO: generate TOC -->
+
+## `p/` - "Pure" packages
+
+A `p/` package denotes a "pure" package within the system. These packages are
+crafted as self-contained units of code, capable of being independently imported
+and utilized.
+
+Unlike `r/` realms, `p/` packages do not possess states or assets. They are
+designed specifically to be called by other packages, whether those packages are
+pure or realms.
+
+## `r/` - "Realm" packages
+
+An `r/` realm designates a package endowed with advanced capabilities, referred
+to as a "realm".
+
+Realms can accommodate a diverse array of data and functionalities, including
+Bank State, Data State, and Address.
+
+They are purposed to furnish and expose features for both user-initiated calls
+and as components invoked by other realm packages.