diff --git a/01_Day_Introduction/01_day_starter/day1_solution/comments.js b/01_Day_Introduction/01_day_starter/day1_solution/comments.js
new file mode 100644
index 0000000..51bb85f
--- /dev/null
+++ b/01_Day_Introduction/01_day_starter/day1_solution/comments.js
@@ -0,0 +1,7 @@
+// comments can make code readable
+// Welcome to 30DaysOfJavaScript
+
+/*
+ comments can make code readable,
+ easy to reuse and informative
+*/
diff --git a/01_Day_Introduction/01_day_starter/day1_solution/datatypes.js b/01_Day_Introduction/01_day_starter/day1_solution/datatypes.js
new file mode 100644
index 0000000..c4ba970
--- /dev/null
+++ b/01_Day_Introduction/01_day_starter/day1_solution/datatypes.js
@@ -0,0 +1,5 @@
+console.log(typeof studentName);
+console.log(typeof learning);
+console.log(typeof age);
+console.log(typeof score);
+console.log(typeof grade);
diff --git a/01_Day_Introduction/01_day_starter/day1_solution/variable.js b/01_Day_Introduction/01_day_starter/day1_solution/variable.js
new file mode 100644
index 0000000..c68db1c
--- /dev/null
+++ b/01_Day_Introduction/01_day_starter/day1_solution/variable.js
@@ -0,0 +1,28 @@
+// Create a variable.js file and declare variables and assign string, boolean, undefined and null data types
+
+let newStudentName = "Mujeeb ur Rahman";
+let learning = true;
+let newAge = 25;
+let score;
+let grad = null;
+
+let firstVariable;
+let secondVariable;
+let thirdVariable;
+let fourthVariable;
+
+let fifthVariable = "fifthVariable";
+let sixthVariable = 6;
+let seventhVariable = true;
+let eighthVariable = 8.0;
+
+let myFirstName = "Mujeeb ur",
+ myLastName = "Rahman",
+ materialStatus = "single",
+ myCountry = "Pakistan",
+ myAge = 30;
+
+let yourAge = 25;
+
+console.log(`I am ${myAge} years old`);
+console.log(`You are ${yourAge} years old`);
diff --git a/01_Day_Introduction/01_day_starter/index.html b/01_Day_Introduction/01_day_starter/index.html
index 7ed5b19..71ce6ec 100644
--- a/01_Day_Introduction/01_day_starter/index.html
+++ b/01_Day_Introduction/01_day_starter/index.html
@@ -1,19 +1,18 @@
<!DOCTYPE html>
<html lang="en">
+ <head>
+ <title>30DaysOfJavaScript</title>
+ </head>
-<head>
- <title>30DaysOfJavaScript</title>
-</head>
-
-<body>
- <h1>30DaysOfJavaScript:03 Day</h1>
- <h2>Introduction</h2>
- <button onclick="alert('Welcome to 30DaysOfJavaScript!');">Click Me</button>
- <script src="./helloworld.js"></script>
- <script src="./introduction.js"></script>
- <script src="./variable.js"></script>
- <script src="./main.js"></script>
-
-</body>
-
-</html>
\ No newline at end of file
+ <body>
+ <h1>30DaysOfJavaScript:03 Day</h1>
+ <h2>Introduction</h2>
+ <button onclick="alert('Welcome to 30DaysOfJavaScript!');">Click Me</button>
+ <script src="./helloworld.js"></script>
+ <script src="./introduction.js"></script>
+ <script src="./variable.js"></script>
+ <script src="./main.js"></script>
+ <script src="./day1_solution/variable.js"></script>
+ <script src="./day1_solution/datatypes.js"></script>
+ </body>
+</html>
diff --git a/01_Day_Introduction/01_day_starter/main.js b/01_Day_Introduction/01_day_starter/main.js
index 2b952bc..c49eeb9 100644
--- a/01_Day_Introduction/01_day_starter/main.js
+++ b/01_Day_Introduction/01_day_starter/main.js
@@ -1,4 +1,5 @@
// the variable values can be accessed from other variable.js file
-console.log(firstName, lastName, country, city, age, isMarried)
-console.log(gravity, boilingPoint, PI) // 9.81, 100, 3.14
-console.log(name, job, live)
\ No newline at end of file
+console.log(firstName, lastName, country, city, age, isMarried);
+console.log(gravity, boilingPoint, PI); // 9.81, 100, 3.14
+console.log(name, job, live);
+console.log(studentName, studentJob, studentLive);
diff --git a/01_Day_Introduction/01_day_starter/variable.js b/01_Day_Introduction/01_day_starter/variable.js
index 62558cb..d2d7a51 100644
--- a/01_Day_Introduction/01_day_starter/variable.js
+++ b/01_Day_Introduction/01_day_starter/variable.js
@@ -1,20 +1,24 @@
// Declaring different variables of different data types
-let firstName = 'Asabeneh' // first name of a person
-let lastName = 'Yetayeh' // last name of a person
-let country = 'Finland' // country
-let city = 'Helsinki' // capital city
-let age = 100 // age in years
-let isMarried = true
+let firstName = "Asabeneh"; // first name of a person
+let lastName = "Yetayeh"; // last name of a person
+let country = "Finland"; // country
+let city = "Helsinki"; // capital city
+let age = 100; // age in years
+let isMarried = true;
// Declaring variables with number values
-const gravity = 9.81 // earth gravity in m/s2
-const boilingPoint = 100 // water boiling point, temperature in oC
-const PI = 3.14 // geometrical constant
+const gravity = 9.81; // earth gravity in m/s2
+const boilingPoint = 100; // water boiling point, temperature in oC
+const PI = 3.14; // geometrical constant
// Variables can also be declaring in one line separated by comma
-let name = 'Asabeneh', //name of a person
- job = 'teacher',
- live = 'Finland'
+let name = "Asabeneh", //name of a person
+ job = "teacher",
+ live = "Finland";
+
+let studentName = "Mujeeb ur Rahman",
+ studentJob = "software learner",
+ studentLive = "Pakistan";