diff --git a/3-Domain/src/main/java/Category/Category.java b/3-Domain/src/main/java/category/Category.java
similarity index 96%
rename from 3-Domain/src/main/java/Category/Category.java
rename to 3-Domain/src/main/java/category/Category.java
index b2a9847..b4404fa 100644
--- a/3-Domain/src/main/java/Category/Category.java
+++ b/3-Domain/src/main/java/category/Category.java
@@ -1,4 +1,4 @@
-package Category;
+package category;
 
 /**
  * A Category that can be assigned to a link to group links with similar content.
diff --git a/3-Domain/src/main/java/Category/CategoryId.java b/3-Domain/src/main/java/category/CategoryId.java
similarity index 67%
rename from 3-Domain/src/main/java/Category/CategoryId.java
rename to 3-Domain/src/main/java/category/CategoryId.java
index d9207f0..1b1a37d 100644
--- a/3-Domain/src/main/java/Category/CategoryId.java
+++ b/3-Domain/src/main/java/category/CategoryId.java
@@ -1,4 +1,4 @@
-package Category;
+package category;
 
 public record CategoryId(int id) {
 }
diff --git a/3-Domain/src/main/java/Category/CategoryName.java b/3-Domain/src/main/java/category/CategoryName.java
similarity index 93%
rename from 3-Domain/src/main/java/Category/CategoryName.java
rename to 3-Domain/src/main/java/category/CategoryName.java
index e86fc6c..1f69c47 100644
--- a/3-Domain/src/main/java/Category/CategoryName.java
+++ b/3-Domain/src/main/java/category/CategoryName.java
@@ -1,6 +1,6 @@
-package Category;
+package category;
 
-import Exeptions.IllegalValueObjectArgument;
+import exeptions.IllegalValueObjectArgument;
 
 import java.util.Objects;
 
diff --git a/3-Domain/src/main/java/Exeptions/IllegalValueObjectArgument.java b/3-Domain/src/main/java/exeptions/IllegalValueObjectArgument.java
similarity index 87%
rename from 3-Domain/src/main/java/Exeptions/IllegalValueObjectArgument.java
rename to 3-Domain/src/main/java/exeptions/IllegalValueObjectArgument.java
index 1092e5e..e5e7ded 100644
--- a/3-Domain/src/main/java/Exeptions/IllegalValueObjectArgument.java
+++ b/3-Domain/src/main/java/exeptions/IllegalValueObjectArgument.java
@@ -1,4 +1,4 @@
-package Exeptions;
+package exeptions;
 
 public class IllegalValueObjectArgument extends Exception {
 
diff --git a/3-Domain/src/test/java/Category/CategoryIdTest.java b/3-Domain/src/test/java/category/CategoryIdTest.java
similarity index 95%
rename from 3-Domain/src/test/java/Category/CategoryIdTest.java
rename to 3-Domain/src/test/java/category/CategoryIdTest.java
index 86f6b82..2130769 100644
--- a/3-Domain/src/test/java/Category/CategoryIdTest.java
+++ b/3-Domain/src/test/java/category/CategoryIdTest.java
@@ -1,4 +1,4 @@
-package Category;
+package category;
 
 import org.junit.jupiter.api.Test;
 
diff --git a/3-Domain/src/test/java/Category/CategoryNameTest.java b/3-Domain/src/test/java/category/CategoryNameTest.java
similarity index 94%
rename from 3-Domain/src/test/java/Category/CategoryNameTest.java
rename to 3-Domain/src/test/java/category/CategoryNameTest.java
index ca46e46..3e21e32 100644
--- a/3-Domain/src/test/java/Category/CategoryNameTest.java
+++ b/3-Domain/src/test/java/category/CategoryNameTest.java
@@ -1,6 +1,6 @@
-package Category;
+package category;
 
-import Exeptions.IllegalValueObjectArgument;
+import exeptions.IllegalValueObjectArgument;
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
diff --git a/3-Domain/src/test/java/Category/CategoryTest.java b/3-Domain/src/test/java/category/CategoryTest.java
similarity index 96%
rename from 3-Domain/src/test/java/Category/CategoryTest.java
rename to 3-Domain/src/test/java/category/CategoryTest.java
index b08f5d9..a0795ae 100644
--- a/3-Domain/src/test/java/Category/CategoryTest.java
+++ b/3-Domain/src/test/java/category/CategoryTest.java
@@ -1,4 +1,4 @@
-package Category;
+package category;
 
 import org.junit.jupiter.api.Test;