diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/AdminEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/AdminEnvironment.java
index 987cd38..9f3b1d2 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/AdminEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/AdminEnvironment.java
@@ -13,6 +13,8 @@ import com.orientechnologies.orient.core.metadata.security.OSecurity;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * This SystemEnvironment is used in all the case the
+ * operation must be done by an administrator 
  */
 public class AdminEnvironment extends SystemEnvironment {
 	
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ContextEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ContextEnvironment.java
index efec709..5934019 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ContextEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ContextEnvironment.java
@@ -11,6 +11,9 @@ import com.orientechnologies.orient.core.metadata.security.ORule;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * This SystemEnvironment is used to pesists
+ * Contexts information and their relations among
+ * others, e.g. a Context is parent of another.
  */
 public class ContextEnvironment extends SystemEnvironment {
 	
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/HierarchicalSystemEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/HierarchicalSystemEnvironment.java
index 56775dd..5946088 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/HierarchicalSystemEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/HierarchicalSystemEnvironment.java
@@ -35,6 +35,10 @@ import com.orientechnologies.orient.core.record.impl.ODocument;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * Base class for all environments which have an hierarchy.
+ * An example is InstanceEnviroment where the instances 
+ * belonging to a context must be visible from parent 
+ * context if the requesting client has enough privileges
  */
 public abstract class HierarchicalSystemEnvironment extends SystemEnvironment {
 	
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/InstanceEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/InstanceEnvironment.java
index c55539e..4b7bddc 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/InstanceEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/InstanceEnvironment.java
@@ -6,6 +6,7 @@ import org.gcube.informationsystem.resourceregistry.api.exceptions.ResourceRegis
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * Contains all the instances belonging to a context.
  */
 public class InstanceEnvironment extends HierarchicalSystemEnvironment {
 
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/QueryTemplateEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/QueryTemplateEnvironment.java
index aac1370..6d95140 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/QueryTemplateEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/QueryTemplateEnvironment.java
@@ -11,6 +11,7 @@ import com.orientechnologies.orient.core.metadata.security.ORule;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * Contains all the query templates
  */
 public class QueryTemplateEnvironment extends SystemEnvironment {
 	
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ShadowContextEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ShadowContextEnvironment.java
index 9a5a285..79c5c7c 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ShadowContextEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/ShadowContextEnvironment.java
@@ -12,6 +12,11 @@ import com.orientechnologies.orient.core.metadata.security.ORule;
 /**
  * @author Luca Frosini (ISTI - CNR)
  * Added for feature #19428
+ * It is used as a sort of cemetery for deleted Contexts. 
+ * e.g the information regarding a deleted context are not
+ * really deleted instead are moved in this partition to
+ * ah historical information and to provide a minimal support for 
+ * Context reborn.
  */
 public class ShadowContextEnvironment extends SystemEnvironment {
 	
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/SystemEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/SystemEnvironment.java
index de260fe..ad7cbe9 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/SystemEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/SystemEnvironment.java
@@ -35,6 +35,10 @@ import com.orientechnologies.orient.core.record.impl.ODocument;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * Base class for any system environment.
+ * In the current implementation it represent a 
+ * partion of a graph which in OrientDB is implemented 
+ * via security.
  */
 public abstract class SystemEnvironment {
 	
diff --git a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/TypeEnvironment.java b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/TypeEnvironment.java
index fc7d093..0ae0883 100644
--- a/src/main/java/org/gcube/informationsystem/resourceregistry/environments/TypeEnvironment.java
+++ b/src/main/java/org/gcube/informationsystem/resourceregistry/environments/TypeEnvironment.java
@@ -11,6 +11,9 @@ import com.orientechnologies.orient.core.metadata.security.ORule;
 
 /**
  * @author Luca Frosini (ISTI - CNR)
+ * Contains all the information-system-model types
+ * plus all the types defined on top of the 
+ * information-system-model (e.g the gcube-model)
  */
 public class TypeEnvironment extends SystemEnvironment {