diff --git a/Models/Calculation.cs b/Models/Calculation.cs
index 3a814cc..a3e89aa 100644
--- a/Models/Calculation.cs
+++ b/Models/Calculation.cs
@@ -20,7 +20,7 @@ public double Calculate()
         return _operator switch
         {
             Operator.Add => _firstValue + _secondValue,
-            Operator.Substract => _firstValue - _secondValue,
+            Operator.Subtract => _firstValue - _secondValue,
             Operator.Multiply => _firstValue * _secondValue,
             Operator.Divide => _firstValue / _secondValue,
             _ => throw new InvalidDataException("Operator not allowed")
diff --git a/Models/Calculator.cs b/Models/Calculator.cs
index 99637a9..eddbc00 100644
--- a/Models/Calculator.cs
+++ b/Models/Calculator.cs
@@ -26,7 +26,7 @@ public static string Calculate(string str)
         return character switch
         {
             OperatorChar.Add => Operator.Add,
-            OperatorChar.Substract => Operator.Substract,
+            OperatorChar.Subtract => Operator.Subtract,
             OperatorChar.Multiply => Operator.Multiply,
             OperatorChar.Divide => Operator.Divide,
             _ => null
@@ -101,7 +101,7 @@ private static int SetIndexOfPreviousOperator(MyStringBuilder calculus, int inde
         // If the first value is negative and not the first calculation, an operator must be just before the index
         // previously calculated as the indexOfPreviousOperator, e.g. in a+-b/c the - isn't previousOperator, it's +
         else if (indexOfPreviousOperator > 0 &&
-                 calculus[indexOfPreviousOperator].Equals(OperatorChar.Substract) && // minus sign
+                 calculus[indexOfPreviousOperator].Equals(OperatorChar.Subtract) && // minus sign
                  OperatorChar.IsAnOperator(calculus[indexOfPreviousOperator - 1])) // previous index contains an operator
         {
             indexOfPreviousOperator--;
diff --git a/Models/Operator.cs b/Models/Operator.cs
index f13bc6b..e0a7d26 100644
--- a/Models/Operator.cs
+++ b/Models/Operator.cs
@@ -3,7 +3,7 @@ namespace Calc.Models;
 public enum Operator
 {
     Add,
-    Substract,
+    Subtract,
     Multiply,
     Divide
 }
\ No newline at end of file
diff --git a/Models/OperatorChar.cs b/Models/OperatorChar.cs
index 0bf1376..c2ae2e4 100644
--- a/Models/OperatorChar.cs
+++ b/Models/OperatorChar.cs
@@ -5,13 +5,13 @@ namespace Calc.Models;
 public static class OperatorChar
 {
     public const char Add = '+';
-    public const char Substract = '-';
+    public const char Subtract = '-';
     public const char Multiply = '*';
     public const char Divide = '/';
     
-    public static readonly char[] Operators = { Add, Substract, Multiply, Divide };
+    public static readonly char[] Operators = { Add, Subtract, Multiply, Divide };
     public static readonly char[] PrecedentOperators = { Multiply, Divide };
-    public static readonly char[] NonPrecedentOperators = { Add, Substract };
+    public static readonly char[] NonPrecedentOperators = { Add, Subtract };
 
     public static bool IsAnOperator(char character)
     {
diff --git a/ViewModels/MainWindowViewModel.cs b/ViewModels/MainWindowViewModel.cs
index 88f102c..48fd7b5 100644
--- a/ViewModels/MainWindowViewModel.cs
+++ b/ViewModels/MainWindowViewModel.cs
@@ -71,7 +71,7 @@ private void AddOperator(Operator @operator)
             ShownString += @operator switch
             {
                 Operator.Add => OperatorChar.Add,
-                Operator.Substract => OperatorChar.Substract,
+                Operator.Subtract => OperatorChar.Subtract,
                 Operator.Multiply => OperatorChar.Multiply,
                 Operator.Divide => OperatorChar.Divide,
                 _ => throw new InvalidDataException("Operator not allowed")
@@ -98,12 +98,12 @@ private void AlternateNegativePositive()
             var indexWhereSetOrUnsetSign = SetIndexWhereToSetOrUnsetSign();
 
             if (ShownString.Length == 0 || ShownString[^1].Equals('('))
-                ShownString += OperatorChar.Substract;
+                ShownString += OperatorChar.Subtract;
             else
             {
                 switch (ShownString[indexWhereSetOrUnsetSign])
                 {
-                    case OperatorChar.Substract:
+                    case OperatorChar.Subtract:
                         if (indexWhereSetOrUnsetSign == 0 ||
                             ShownString[indexWhereSetOrUnsetSign - 1].Equals('(') ||
                             OperatorChar.IsAnOperator(ShownString[indexWhereSetOrUnsetSign - 1]))
@@ -112,13 +112,13 @@ private void AlternateNegativePositive()
                         else
                             // Add -
                             ShownString = ShownString[..indexWhereSetOrUnsetSign] +
-                                          OperatorChar.Substract +
+                                          OperatorChar.Subtract +
                                           ShownString[indexWhereSetOrUnsetSign..];
                         break;
                     default:
                         // Add -
                         ShownString = ShownString[..indexWhereSetOrUnsetSign] +
-                                      OperatorChar.Substract +
+                                      OperatorChar.Subtract +
                                       ShownString[indexWhereSetOrUnsetSign..];
                         break;
                 }
@@ -197,7 +197,7 @@ private int SetIndexWhereToSetOrUnsetSign()
             char[] nonSubstractOperators = { OperatorChar.Add, OperatorChar.Multiply, OperatorChar.Divide };
             
             var indexAfterLastNonSubstractOperator = ShownString.LastIndexOfAny(nonSubstractOperators) + 1;
-            var indexOfLastSubstractOperator = ShownString.LastIndexOf(OperatorChar.Substract);
+            var indexOfLastSubstractOperator = ShownString.LastIndexOf(OperatorChar.Subtract);
             var indexAfterLastParenthesis = ShownString.LastIndexOf('(') + 1;
             var indexLastOperator = MaxOf(indexAfterLastNonSubstractOperator, indexOfLastSubstractOperator);
 
diff --git a/Views/MainWindow.axaml b/Views/MainWindow.axaml
index 401df05..f197b91 100644
--- a/Views/MainWindow.axaml
+++ b/Views/MainWindow.axaml
@@ -37,7 +37,7 @@
     </Window.Styles>
 
     <Window.KeyBindings>
-        <!-- 0 -->
+        <!--  0  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D0">
             <KeyBinding.CommandParameter>
                 <system:Int32>0</system:Int32>
@@ -48,7 +48,7 @@
                 <system:Int32>0</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 1 -->
+        <!--  1  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D1">
             <KeyBinding.CommandParameter>
                 <system:Int32>1</system:Int32>
@@ -59,7 +59,7 @@
                 <system:Int32>1</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 2 -->
+        <!--  2  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D2">
             <KeyBinding.CommandParameter>
                 <system:Int32>2</system:Int32>
@@ -70,7 +70,7 @@
                 <system:Int32>2</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 3 -->
+        <!--  3  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D3">
             <KeyBinding.CommandParameter>
                 <system:Int32>3</system:Int32>
@@ -81,7 +81,7 @@
                 <system:Int32>3</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 4 -->
+        <!--  4  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D4">
             <KeyBinding.CommandParameter>
                 <system:Int32>4</system:Int32>
@@ -92,7 +92,7 @@
                 <system:Int32>4</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 5 -->
+        <!--  5  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D5">
             <KeyBinding.CommandParameter>
                 <system:Int32>5</system:Int32>
@@ -103,7 +103,7 @@
                 <system:Int32>5</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 6 -->
+        <!--  6  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D6">
             <KeyBinding.CommandParameter>
                 <system:Int32>6</system:Int32>
@@ -114,7 +114,7 @@
                 <system:Int32>6</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 7 -->
+        <!--  7  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D7">
             <KeyBinding.CommandParameter>
                 <system:Int32>7</system:Int32>
@@ -125,7 +125,7 @@
                 <system:Int32>7</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 8 -->
+        <!--  8  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D8">
             <KeyBinding.CommandParameter>
                 <system:Int32>8</system:Int32>
@@ -136,7 +136,7 @@
                 <system:Int32>8</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- 9 -->
+        <!--  9  -->
         <KeyBinding Command="{Binding AddNumberCommand}" Gesture="D9">
             <KeyBinding.CommandParameter>
                 <system:Int32>9</system:Int32>
@@ -147,7 +147,7 @@
                 <system:Int32>9</system:Int32>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- + -->
+        <!--  +  -->
         <KeyBinding Command="{Binding AddOperatorCommand}" Gesture="Add">
             <KeyBinding.CommandParameter>
                 <m:Operator>Add</m:Operator>
@@ -158,34 +158,34 @@
                 <m:Operator>Add</m:Operator>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- - -->
+        <!--  -  -->
         <KeyBinding Command="{Binding AddOperatorCommand}" Gesture="Subtract">
             <KeyBinding.CommandParameter>
-                <m:Operator>Substract</m:Operator>
+                <m:Operator>Subtract</m:Operator>
             </KeyBinding.CommandParameter>
         </KeyBinding>
         <KeyBinding Command="{Binding AddOperatorCommand}" Gesture="OemMinus">
             <KeyBinding.CommandParameter>
-                <m:Operator>Substract</m:Operator>
+                <m:Operator>Subtract</m:Operator>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- . -->
-        <KeyBinding Command="{Binding AddDecimalSeparatorCommand}" Gesture="OemPeriod"/>
-        <!-- +- -->
+        <!--  .  -->
+        <KeyBinding Command="{Binding AddDecimalSeparatorCommand}" Gesture="OemPeriod" />
+        <!--  +-  -->
         <KeyBinding Command="{Binding AlternateNegativePositiveCommand}" Gesture="Alt+Subtract" />
         <KeyBinding Command="{Binding AlternateNegativePositiveCommand}" Gesture="Alt+OemMinus" />
-        <!-- Backspace -->
-        <KeyBinding Command="{Binding DeleteLastCommand}" Gesture="Back"/>
-        <!-- Delete -->
-        <KeyBinding Command="{Binding ClearScreenCommand}" Gesture="Escape"/>
-        <KeyBinding Command="{Binding ClearScreenCommand}" Gesture="Delete"/>
-        <!-- * -->
+        <!--  Backspace  -->
+        <KeyBinding Command="{Binding DeleteLastCommand}" Gesture="Back" />
+        <!--  Delete  -->
+        <KeyBinding Command="{Binding ClearScreenCommand}" Gesture="Escape" />
+        <KeyBinding Command="{Binding ClearScreenCommand}" Gesture="Delete" />
+        <!--  *  -->
         <KeyBinding Command="{Binding AddOperatorCommand}" Gesture="Multiply">
             <KeyBinding.CommandParameter>
                 <m:Operator>Multiply</m:Operator>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- / -->
+        <!--  /  -->
         <KeyBinding Command="{Binding AddOperatorCommand}" Gesture="Divide">
             <KeyBinding.CommandParameter>
                 <m:Operator>Divide</m:Operator>
@@ -196,13 +196,13 @@
                 <m:Operator>Divide</m:Operator>
             </KeyBinding.CommandParameter>
         </KeyBinding>
-        <!-- () -->
+        <!--  ()  -->
         <KeyBinding Command="{Binding AddParenthesisCommand}" Gesture="OemOpenBrackets" />
         <KeyBinding Command="{Binding AddParenthesisCommand}" Gesture="OemCloseBrackets" />
-        <!-- = -->
+        <!--  =  -->
         <KeyBinding Command="{Binding PickResultCommand}" Gesture="Enter" />
     </Window.KeyBindings>
- 
+
     <Grid Margin="5" RowDefinitions="Auto, Auto, *">
         <!--  Screens  -->
         <TextBlock
@@ -366,7 +366,7 @@
                 Grid.Column="4"
                 Grid.Row="2">
                 <Button.CommandParameter>
-                    <m:Operator>Substract</m:Operator>
+                    <m:Operator>Subtract</m:Operator>
                 </Button.CommandParameter>
                 <material:MaterialIcon Kind="Minus" />
             </Button>