diff --git a/calculator.rb b/calculator.rb
new file mode 100644
index 0000000..10e669f
--- /dev/null
+++ b/calculator.rb
@@ -0,0 +1,72 @@
+### ALL DEFINED METHODS
+# Create class method to check if strings are numeric
+class String
+  def numeric?
+    Float(self) != nil rescue false
+  end
+end
+# Method for validating number inputs
+def val(number_to_val)
+   # Call class String method to check
+  # Alternative? --> while (number_to_val != '0' && number_to_val.to_i.to_f.to_s != number_to_val.strip)
+  unless number_to_val.numeric?
+    puts "Please enter a valid integer" ## CONTINUE TO STAY TRUE
+    number_to_val = gets.chomp
+  end
+  return number_to_val
+end
+# Method for validating operator
+def val_op(op_to_val)
+  until ["+", "ADD", "-", "SUBTRACT", "*", "MULTIPLY", "/", "DIVIDE"].include?(op_to_val) ## UNTIL FALSE
+    puts "Please enter a valid operator"
+    op_to_val = gets.chomp.upcase
+  end
+  return op_to_val
+end
+# Method to run final calculations based on choices
+def calc(op_type, num_1, num_2)
+  # Conditional to run calulations based on operator choice
+  case op_type
+    when "+", "ADD"
+      return num_1 + num_2
+    when "-", "MINUS"
+      return num_1 - num_2
+    when "*", "MULTIPLY"
+      return num_1 * num_2
+    else
+      return num_1 / num_2
+  end
+end
+#########################################################################
+##################### THIS IS WHERE IT ALL BEGINS #######################
+#########################################################################
+puts "======== WELCOME TO CALCULATOR ========"
+puts
+### GET FIRST NUMBER - CALL METHOD - VALIDATE - RETURN VALUE: STRING
+puts "First number to calculate?"
+input_num_1 = gets.chomp #10
+returned_num_1 = val(input_num_1)
+
+### GET OPERATOR - CALL METHOD - VALIDATE - RETURN VALUE: STRING
+puts "What would you like to do? +, -, /, *"
+input_oper = gets.chomp.upcase
+returned_op = val_op(input_oper)
+
+### GET SECOND NUMBER - CALL METHOD - VALIDATE - RETURN VALUE: STRING
+puts "Second number to calculate?"
+input_num_2 = gets.chomp
+returned_num_2 = val(input_num_2)
+
+### CONVERT INPUT NUMBERS TO FLOATS IN CASE OF DECIMAL PLACES
+num_1, num_2 = returned_num_1.to_f, returned_num_2.to_f
+
+### CALL CALCULATION METHOD TO GET FINAL RETURNED CALCULATION
+returned_calc = calc(returned_op, num_1, num_2)
+
+### DISPLAY FIXNUM IF ONLY FIXNUMS
+if returned_calc % 1 == 0 # INTEGERS WILL ALWAYS HAVE REMAINDER 0 IF DIVDED BY ONE
+  returned_calc = returned_calc.to_i
+  puts "Your requested calculation is: #{returned_calc}"
+else
+  puts "Your requested calculation is: #{returned_calc}"
+end