diff --git a/pandas/Average Salary of Each Department.py b/pandas/Average Salary of Each Department.py
new file mode 100644
index 00000000..ac282d5d
--- /dev/null
+++ b/pandas/Average Salary of Each Department.py	
@@ -0,0 +1,14 @@
+Employee = pd.DataFrame({
+    'id': [1, 2, 3, 4],
+    'name': ['Alice', 'Bob', 'Charlie', 'David'],
+    'salary': [5000, 7000, 6000, 8000],
+    'departmentId': [1, 1, 2, 2]
+})
+Department = pd.DataFrame({
+    'id': [1, 2],
+    'name': ['HR', 'Engineering']
+})
+
+merged = Employee.merge(Department, left_on='departmentId', right_on='id')
+result = merged.groupby('name_y', as_index=False)['salary'].mean().rename(columns={'name_y': 'department'})
+print(result)
diff --git a/pandas/Customers Who Never Ordered.py b/pandas/Customers Who Never Ordered.py
new file mode 100644
index 00000000..89152990
--- /dev/null
+++ b/pandas/Customers Who Never Ordered.py	
@@ -0,0 +1,12 @@
+Customers = pd.DataFrame({
+    'id': [1, 2, 3],
+    'name': ['Alice', 'Bob', 'Charlie']
+})
+Orders = pd.DataFrame({
+    'id': [1, 2],
+    'customerId': [1, 2]
+})
+
+merged = Customers.merge(Orders, left_on='id', right_on='customerId', how='left')
+result = merged[merged['customerId'].isna()][['name']]
+print(result)
diff --git a/pandas/Department Highest Salary.py b/pandas/Department Highest Salary.py
new file mode 100644
index 00000000..56c1b8c2
--- /dev/null
+++ b/pandas/Department Highest Salary.py	
@@ -0,0 +1,16 @@
+Employee = pd.DataFrame({
+    'id': [1, 2, 3, 4],
+    'name': ['Alice', 'Bob', 'Charlie', 'David'],
+    'salary': [5000, 7000, 6000, 7000],
+    'departmentId': [1, 1, 2, 2]
+})
+
+Department = pd.DataFrame({
+    'id': [1, 2],
+    'name': ['HR', 'Engineering']
+})
+
+merged = Employee.merge(Department, left_on='departmentId', right_on='id', suffixes=('', '_dept'))
+max_salary = merged.groupby('departmentId')['salary'].transform('max')
+result = merged[merged['salary'] == max_salary][['name_dept', 'name', 'salary']]
+print(result)
diff --git a/pandas/Employees Earning More Than Their Managers.py b/pandas/Employees Earning More Than Their Managers.py
new file mode 100644
index 00000000..fcc173cb
--- /dev/null
+++ b/pandas/Employees Earning More Than Their Managers.py	
@@ -0,0 +1,13 @@
+import pandas as pd
+
+data = {
+    'id': [1, 2, 3, 4],
+    'name': ['Alice', 'Bob', 'Charlie', 'David'],
+    'salary': [5000, 7000, 6000, 8000],
+    'managerId': [None, 1, 1, 2]
+}
+Employee = pd.DataFrame(data)
+
+df = Employee.merge(Employee, left_on='managerId', right_on='id', suffixes=('', '_manager'))
+result = df[df['salary'] > df['salary_manager']][['name']]
+print(result)
diff --git a/pandas/Second Highest Salary.py b/pandas/Second Highest Salary.py
new file mode 100644
index 00000000..037febac
--- /dev/null
+++ b/pandas/Second Highest Salary.py	
@@ -0,0 +1,6 @@
+Employee = pd.DataFrame({
+    'id': [1, 2, 3],
+    'salary': [100, 200, 300]
+})
+second_highest = Employee['salary'].drop_duplicates().nlargest(2).min()
+print(second_highest)