diff --git a/app.py b/app.py
index 120e654..fdffb25 100644
--- a/app.py
+++ b/app.py
@@ -9,6 +9,32 @@ from pathlib import Path
 from influxdb_client import InfluxDBClient
 from datetime import datetime, timedelta
 from collections import defaultdict
+from datetime import datetime
+import shutil
+import logging
+import platform
+# --------------------------------------------------
+# Logging
+# --------------------------------------------------
+
+if platform.system() == "Windows":
+    log_dir = Path(__file__).parent / "logs"
+else:
+    log_dir = Path.home() / "logs"
+category_logger = logging.getLogger("categories")
+log_dir.mkdir(exist_ok=True)
+
+log_file = log_dir / "ing.log"
+
+logging.basicConfig(
+    filename=log_file,
+    level=logging.INFO,
+    format="%(asctime)s [%(levelname)s] %(message)s",
+)
+
+logging.info(
+    "[app.py] === Scriptstart ==="
+)
 
 app = Flask(__name__)
 
@@ -557,7 +583,16 @@ def delete_category(category):
         "w",
         encoding="utf-8"
     ) as f:
-
+        if CATEGORIES_FILE.exists():
+            shutil.copy2(
+                CATEGORIES_FILE,
+                str(CATEGORIES_FILE) + ".bak"
+            )
+        logging.warning(
+            f"Kategorien werden gespeichert. "
+            f"Anzahl Kategorien={len(categories)} "
+            f"Keys={list(categories.keys())}"
+        )
         json.dump(
             categories,
             f,
@@ -589,7 +624,16 @@ def add_category():
         "w",
         encoding="utf-8"
     ) as f:
-
+        if CATEGORIES_FILE.exists():
+            shutil.copy2(
+                CATEGORIES_FILE,
+                str(CATEGORIES_FILE) + ".bak"
+            )
+        logging.warning(
+            f"Kategorien werden gespeichert. "
+            f"Anzahl Kategorien={len(categories)} "
+            f"Keys={list(categories.keys())}"
+        )
         json.dump(
             categories,
             f,
@@ -645,7 +689,16 @@ def add_word(category):
         "w",
         encoding="utf-8"
     ) as f:
-
+        if CATEGORIES_FILE.exists():
+            shutil.copy2(
+                CATEGORIES_FILE,
+                str(CATEGORIES_FILE) + ".bak"
+            )
+        logging.warning(
+            f"Kategorien werden gespeichert. "
+            f"Anzahl Kategorien={len(categories)} "
+            f"Keys={list(categories.keys())}"
+        )
         json.dump(
             categories,
             f,
@@ -679,7 +732,16 @@ def delete_word(category, word):
         "w",
         encoding="utf-8"
     ) as f:
-
+        if CATEGORIES_FILE.exists():
+            shutil.copy2(
+                CATEGORIES_FILE,
+                str(CATEGORIES_FILE) + ".bak"
+            )
+        logging.warning(
+            f"Kategorien werden gespeichert. "
+            f"Anzahl Kategorien={len(categories)} "
+            f"Keys={list(categories.keys())}"
+        )
         json.dump(
             categories,
             f,