Added basic glossary

Glossary.md

@@ -0,0 +1,21 @@
+## App
+Software using `ubisync` by connecting to the locally installed `ubisync` instance
+
+## Element
+Smallest individually shareable chunk of data. May contain data of arbitrary structure. Write conflicts (different peers modifying content simultaneously) can only occur within an element. Peers modifying different elements simultaneously must not cause write conflicts. An Element belongs to exactly one pot
+
+## Family
+A group of peers which assume absolute trust among each other. A peer can demand any elements, pots, etc. from its family members without permission checks. Peers proactively share the metadata of their pots within their family to allow others to subscribe to data they are interested in.
+
+## Message
+Data format used in communication between peers. They can contain administrative data (like resolving a peer's name), or payload data (like element updates, creations etc.).
+
+## Peer
+Peers are actors within the `ubisync` network. They provide a way for apps to share data to other peers, manage and search it. A peer has exactly one active I2P identity at any given time.
+
+In the common use case, a peer represents one device of a user, while the family represents the user himself (as the collection of all of his devices).
+
+## Pot
+Group of elements, every element belongs to exactly one pot. A pot is created with an app type, suggesting a way the elements may be used. Thus, the pot and its app type provides context to the loose collection of tagged elements inside it.
+
+Typically, an application using ubisync uses exactly one pot to store all its data. When an app on a different peer uses the same pot, they have a common view on the data and can be called "synchronized"