diff --git a/Challenges/Day_2/backup_with_rotation.sh b/Challenges/Day_2/backup_with_rotation.sh
index 2c5e56f..234f5f4 100644
--- a/Challenges/Day_2/backup_with_rotation.sh
+++ b/Challenges/Day_2/backup_with_rotation.sh
@@ -1,41 +1,24 @@
-#!/bin/bash
-
-# Function to display usage information and available options
-function display_usage {
-    echo "Usage: $0 /path/to/source_directory"
-}
-
-# Check if a valid directory path is provided as a command-line argument
-if [ $# -eq 0 ] || [ ! -d "$1" ]; then
-    echo "Error: Please provide a valid directory path as a command-line argument."
-    display_usage
-    exit 1
-fi
-
-# Directory path of the source directory to be backed up
-source_dir="$1"
 
-# Function to create a timestamped backup folder
-function create_backup {
-    local timestamp=$(date '+%Y-%m-%d_%H-%M-%S')  # Get the current timestamp
-    local backup_dir="${source_dir}/backup_${timestamp}"
+###################################################################
+# Author: Sasiram Beeke
+# Date: 01/08/2023
+# Description: Interactive File and Directory Explorer
+# Tip: to execute shell give permision +x scriptname
+###################################################################
 
-    # Create the backup folder with the timestamped name
-    mkdir "$backup_dir"
-    echo "Backup created successfully: $backup_dir"
-}
-
-# Function to perform the rotation and keep only the last 3 backups
-function perform_rotation {
-    local backups=($(ls -t "${source_dir}/backup_"* 2>/dev/null))  # List existing backups sorted by timestamp
-
-    # Check if there are more than 3 backups
-    if [ "${#backups[@]}" -gt 3 ]; then
-        local backups_to_remove="${backups[@]:3}"  # Get backups beyond the last 3
-        rm -rf "${backups_to_remove[@]}"  # Remove the oldest backups
-    fi
-}
-
-# Main script logic
-create_backup
-perform_rotation
+#!/bin/bash
+# accept argument and assing it to source_dir variable
+source_dir=$1
+# create timestamp and store it to timestamp variable
+timestamp=$(date +%Y-%m-%d-%H-%M-%S)
+# Create the backup folder name using the timestamp
+dir_name="backup_${timestamp}"
+backup_folder="${source_dir}/${dir_name}"
+mkdir "${backup_folder}"
+#The script uses rsync to copy the contents of the source directory to the backup folder. 
+#The rsync command ensures that the backup folder itself is excluded from the copy.
+rsync -av --exclude="${dir_name}" "$source_dir/" "$backup_folder"
+# Find and remove older backups, retaining only the last 3 backups
+find "$source_dir" -maxdepth 1 -type d -name "backup_*" | sort | head -n -3 | xargs rm -rf
+# Print a success message
+echo "Backup created: $backup_folder"
diff --git a/Challenges/Day_2/explorer.sh b/Challenges/Day_2/explorer.sh
index be62ca1..42a99aa 100644
--- a/Challenges/Day_2/explorer.sh
+++ b/Challenges/Day_2/explorer.sh
@@ -1,23 +1,23 @@
-#!/bin/bash
 
-# Part 1: File and Directory Exploration
-echo "Welcome to the Interactive File and Directory Explorer!"
+###################################################################
+# Author: Sasiram Beeke
+# Date: 01/08/2023
+# Description: Interactive File and Directory Explorer
+# Tip: to execute shell give permision +x scriptname
+###################################################################
 
+#!/bin/bash
+echo "Welcome to the Interactive File and Directory Explorer!"
+echo "Files and Directories in the Current Path:"
+ls -lh| awk '{print $9, "(" $5 ")"}'
 while true; do
-    # List all files and directories in the current path
-    echo "Files and Directories in the Current Path:"
-    ls -lh
-
-    # Part 2: Character Counting
-    read -p "Enter a line of text (Press Enter without text to exit): " input
+ # Ask the user if they want to exit the explorer
+    read -p "Enter a line of text (press Enter without text to exit):" input
 
-    # Exit if the user enters an empty string
-    if [ -z "$input" ]; then
-        echo "Exiting the Interactive Explorer. Goodbye!"
+    # Check the user's choice
+    if [[ -z "$input" ]];then
         break
     fi
-
-    # Calculate and print the character count for the input line
-    char_count=$(echo -n "$input" | wc -m)
-    echo "Character Count: $char_count"
+     echo "Character count:$(echo -n "$input" | wc -m)"  
 done
+    echo "Exiting the Interactive Explorer. Goodbye!"
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f1.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f2.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-13/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-13/f1.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-13/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-13/f2.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-13/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-13/f3.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-19-01/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-19-01/f1.txt
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index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-19-01/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-19-01/f2.txt
new file mode 100644
index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-19-01/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-19-01/f3.txt
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index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f1.txt
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index 0000000..e69de29
diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f1.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/f1.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-21-16/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-21-16/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-19-01/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-19-01/f1.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-19-01/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-19-01/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f1.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/backup_2023-08-01-16-19-01/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/backup_2023-08-01-16-21-13/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/f1.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/backup_2023-08-01-16-21-16/f3.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/f1.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/f1.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/f2.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/f2.txt
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diff --git a/Challenges/Day_2/test/backup_2023-08-01-16-22-21/f3.txt b/Challenges/Day_2/test/backup_2023-08-01-16-22-21/f3.txt
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diff --git a/Challenges/Day_2/test/f1.txt b/Challenges/Day_2/test/f1.txt
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diff --git a/Challenges/Day_2/test/f2.txt b/Challenges/Day_2/test/f2.txt
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diff --git a/Challenges/Day_2/test/f3.txt b/Challenges/Day_2/test/f3.txt
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diff --git a/Challenges/Day_2/test1/f4.txt b/Challenges/Day_2/test1/f4.txt
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diff --git a/Challenges/Day_2/test1/f5.txt b/Challenges/Day_2/test1/f5.txt
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diff --git a/Challenges/Day_2/test1/f6.txt b/Challenges/Day_2/test1/f6.txt
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diff --git a/Challenges/Day_2/test3/f7.txt b/Challenges/Day_2/test3/f7.txt
new file mode 100644
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diff --git a/Challenges/Day_2/test3/f8.txt b/Challenges/Day_2/test3/f8.txt
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diff --git a/Challenges/Day_2/test3/f9.txt b/Challenges/Day_2/test3/f9.txt
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diff --git a/Challenges/Day_3/user_management.sh b/Challenges/Day_3/user_management.sh
new file mode 100755
index 0000000..17281d5
--- /dev/null
+++ b/Challenges/Day_3/user_management.sh
@@ -0,0 +1,125 @@
+#!/bin/bash
+# check if a username exists
+username_exists() {
+    if id "$1" &>/dev/null; then
+        return 0 # Username exists
+    else
+        return 1 # Username does not exist
+    fi
+}
+
+# create a new user account
+create_user() {
+    read -p "Enter the new username: " new_username
+    if username_exists "$new_username"; then
+        echo "Error: Username already exists. Please choose a different username."
+        exit 1
+    fi
+
+    read -s -p "Enter the password for the new user: " new_password
+    echo
+    read -s -p "Confirm the password: " confirm_password
+    echo
+
+    if [ "$new_password" != "$confirm_password" ]; then
+        echo "Error: Passwords do not match. User account creation failed."
+        exit 1
+    fi
+
+    # Create the new user account
+    sudo useradd -m "$new_username" &>/dev/null
+    echo "$new_username:$new_password" | sudo chpasswd
+    echo "User account '$new_username' created successfully."
+}
+
+# delete an existing user account
+delete_user() {
+    read -p "Enter the username to be deleted: " del_username
+    if ! username_exists "$del_username"; then
+        echo "Error: Username does not exist. Deletion failed."
+        exit 1
+    fi
+
+    # Delete the user account
+    sudo userdel -r "$del_username" &>/dev/null
+    echo "User account '$del_username' deleted successfully."
+}
+
+# reset the password of an existing user account
+reset_password() {
+    read -p "Enter the username for password reset: " reset_username
+    if ! username_exists "$reset_username"; then
+        echo "Error: Username does not exist. Password reset failed."
+        exit 1
+    fi
+
+    read -s -p "Enter the new password for the user: " new_password
+    echo
+    read -s -p "Confirm the new password: " confirm_password
+    echo
+
+    if [ "$new_password" != "$confirm_password" ]; then
+        echo "Error: Passwords do not match. Password reset failed."
+        exit 1
+    fi
+
+    # Reset the user's password
+    echo "$reset_username:$new_password" | sudo chpasswd
+    echo "Password for user '$reset_username' reset successfully."
+}
+
+# list all user accounts on the system
+list_users() {
+    echo "List of user accounts:"
+    echo "Username      UID"
+    echo "-----------------"
+#    cut -d: -f1,3 /etc/passwd
+while IFS=: read -r username _ uid _; do
+	echo "- $username   (UID: $uid)"
+    done < /etc/passwd
+}
+
+# display usage information and available options
+usage() {
+    echo "Usage: $0 [options]"
+    echo "Options:"
+    echo "  -c, --create    Create a new user account"
+    echo "  -d, --delete    Delete an existing user account"
+    echo "  -r, --reset     Reset the password of an existing user account"
+    echo "  -l, --list      List all user accounts on the system"
+    echo "  -h, --help      Display this help message"
+}
+
+# Main script starts here
+# Check if there are any command-line arguments
+if [ $# -eq 0 ]; then
+    usage
+    exit 1
+fi
+while [[ $# -gt 0 ]]; do
+    key="$1"
+
+    case $key in
+        -c|--create)
+            create_user
+            ;;
+        -d|--delete)
+            delete_user
+            ;;
+        -r|--reset)
+            reset_password
+            ;;
+        -l|--list)
+            list_users
+            ;;
+        -h|--help)
+            usage
+            ;;
+        *)
+            echo "Error: Invalid option. Use -h or --help to see available options."
+            exit 1
+            ;;
+    esac
+    shift
+done
+
diff --git a/Challenges/day1_solution.script.sh b/Challenges/day1_solution.script.sh
new file mode 100755
index 0000000..e6ad78f
--- /dev/null
+++ b/Challenges/day1_solution.script.sh
@@ -0,0 +1,62 @@
+#####################################################################################
+# Author: Sasiram Beeke
+# Date: 31/07/2023
+# Description: Basics of shell scripting.
+# Tip: to execute shell give permision +x scriptname
+#####################################################################################
+
+#!/bin/bash
+echo '############### Task1 Comments start here #####################################'
+echo '############### With single lineComment #######################################'
+echo "welcome to my first example for single line comment"
+#echo "this line us for comment purpose"
+echo "single line comment  example ends here" ## in this by usng # symbol we can give single line comment
+echo '############### using << With multi line comment ##############################'
+<<EOF
+echo "this is example for multi line comment"
+echo "multi line comment example"
+EOF
+echo 'after multiline comment code print here' # in this by usng << multiline comment in used.
+echo '############ using : operator with multi line comment #########################'
+: '
+echo "this is first line"
+echo "this is second line"
+echo "this is third line"
+'
+echo "this is fourth line"  # in this by using : operator multiline commnet is used.
+echo '##################Task1 Comments ends here ####################################'
+
+echo '################## Task2 echo starts here #####################################'
+echo "echo is used to display text or message in terminal"
+echo "welcome to the shell scripting"  #in this both echo statement prints whatever message is gien to display in terminal
+echo '################## Task2 echo Ends here #######################################'
+
+echo '################# Task3 variables starts here #################################'
+name="sasiram beeke"
+echo "my name is $name"
+address='pune'
+echo "I am from $address"
+echo "I am $name and i am from $address" #in this name and address are variables which are used to store values.
+echo '################# Task3 variables ends here ###################################'
+
+echo '################## Task4 using variables addition starts here #################'
+echo 'Enter first number'
+read a
+echo 'Enter second number'
+read b
+echo "Addition for $a and $b is:- $((a+b))"  #it will accept user input and print addition of it
+echo '################## Task4 using variables addition ends here ###################'
+
+echo '################## Task5 built-in variables starts here #######################'
+echo "todays date is `date`" ##describe current date
+echo "$0"  ##describe name of your file or script
+echo "$#"  ##describe number of arguments passed to the script
+echo "$USER"  ##desribe current username of the user
+echo "$SHELL" ##describe path to the shell program being used
+echo '################## Task5 built-in variables ends here #########################'
+
+echo '################### Task6 wildcards starts here ###############################'
+echo "All text files which are available in current directory:"
+ls *.txt  #it will display all text files using * wildcard
+echo '################### Task6 wildcards ends here #################################'
+