diff --git a/interfaceProject/Program.cs b/interfaceProject/Program.cs
new file mode 100644
index 00000000..63bf8ce6
--- /dev/null
+++ b/interfaceProject/Program.cs
@@ -0,0 +1,72 @@
+using System;
+using System.Collections.Generic;
+
+namespace interfaceProject
+{
+    public interface IYearly
+    {
+      int findYearlySalary();
+    }
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Developer d1 = new Developer(40000);
+            Developer d2 = new Developer(90000);
+
+            Contractor c1 = new Contractor(400);
+            Contractor c2 = new Contractor(700);
+
+            Engineer e1 = new Engineer(4000);
+            Engineer e2 = new Engineer(8000);
+
+            List<IYearly> yearlySalaries = new List<IYearly>();
+        }
+    }
+
+    class Developer
+    {
+        public int yearlySalary;
+
+        public Developer(int yearly)
+        {
+            this.yearlySalary = yearly;
+        }
+
+        public int findYearlySalary()
+        {
+            return yearlySalary;
+        }
+
+    }
+
+    class Contractor
+    {
+        public int weeklySalary;
+
+        public Contractor(int weekly)
+        {
+            this.weeklySalary = weekly;
+        }
+
+        public int findYearlySalary()
+        {
+            return weeklySalary*52;
+        }
+    }
+
+    class Engineer
+    {
+        public int monthlySalary;
+
+        public Engineer(int monthly)
+        {
+            this.monthlySalary = monthly;
+        }
+
+        public int findYearlySalary()
+        {
+            return monthlySalary*12;
+        }
+    }
+}
diff --git a/interfaceProject/interfaceProject.csproj b/interfaceProject/interfaceProject.csproj
new file mode 100644
index 00000000..23df6047
--- /dev/null
+++ b/interfaceProject/interfaceProject.csproj
@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>