diff --git a/entity/Contact_entity/documentation.adoc b/entity/Contact_entity/documentation.adoc
index 0d02f16097e4550a414328f833e51a548b546bd5..8a1f2ff91696dd8bb4b7aefea594d5605e359d78 100644
--- a/entity/Contact_entity/documentation.adoc
+++ b/entity/Contact_entity/documentation.adoc
@@ -1,3 +1,33 @@
 = Contact_entity
 
-Represents a Contact without detail information to Organisations/Persons
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+WARNING: Do not confuse this entity with the `Person_entity`. The `Person_entity` is the representation of a person-contact, 
+while the `Contact_entity` is used for further contacts from a perspective of a single person-contact.
+
+Represents a Contact without detail information to Organisations/Persons and is used for displaying and creating
+further (=other) contacts in correlation of a single person-contact.
+
+== Example:
+A person (not a person-contact but a person) has in summary 3 contacts:
+
+- Person: "Maddison Shepard"
+- Person-contact in Organisation "MUX Ltd."
+- Person-contact in Organisation "Shepard Ships Org"
+- Person-contact as a private person
+
+From _Maddison Shepard @ MUX Ltd._'s perspective you can see the further contacts 
+_Maddison Shepard @ Shepard Ships Org_
+and the 
+_private person Maddison Shepard_.
+
+
+From _Maddison Shepard @ Shepard Ships Org_'s perspective you can see the further contacts 
+_Maddison Shepard @ MUX Ltd._
+and the 
+_private person Maddison Shepard_
+and so on.
+These "further contacts" is what the Contact_entity actually is. (this corresponds both display and modifying-mode)
+
+== Why another entity?
+You only want to create a new entry within the `CONTACT`-db-table but not in the `PERSON`-db-table when creatging a new [further] contact
+to an existing person-contact. But - right now - it's only possible to set the "readonly" property within a db-record-container per table as a static configuration but not dynamically.
+This is the reason why we've got to use a very similar but more basic entity where the `PERSON`-db-table is _readonly_ (=the `Contact_entity`).
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