diff --git a/Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-graphical/sumator-graphical.md b/Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-graphical/sumator-graphical.md
index 9c120dca1..b6eff7d5d 100644
--- a/Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-graphical/sumator-graphical.md
+++ b/Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-graphical/sumator-graphical.md
@@ -1,4 +1,4 @@
-# Lab: Graphical Application "Sumator" (Calculator)
+# Lab: Graphical Application "Summator" (Calculator)
 
 Write a **graphical \(GUI\) application**, which **calculates the sum of two numbers**:
 
@@ -31,7 +31,7 @@ We download from the bar on the left \(Toolbox\) **three text boxes** \(`TextBox
 * `buttonCalculate` -> `Calculate`
 * `label1` -> `+`
 * `label2` -> `=`
-* `Form1` -> `Sumator`
+* `Form1` -> `Summator`
 
 ![](/assets/chapter-1-images/07.Numbers-sum-05.png)
 
diff --git a/SUMMARY.md b/SUMMARY.md
index ed29b0d64..c82e72d8d 100644
--- a/SUMMARY.md
+++ b/SUMMARY.md
@@ -19,7 +19,7 @@
     * [Problem: Rectangle Area](Content/Chapter-1-first-steps-in-programming/exercises-first-steps-in-coding/rectangle-area.md)
     * [\* Problem: Square of Stars](Content/Chapter-1-first-steps-in-programming/exercises-first-steps-in-coding/square-of-stars.md)
   * [Lab: Graphical and Web Apps](Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/exercises-graphical-and-web-apps.md)
-    * [Lab: Graphical Application "Sumator"](Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-graphical/sumator-graphical.md)
+    * [Lab: Graphical Application "Summator"](Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-graphical/sumator-graphical.md)
     * [Lab: Web Application "Sumator"](Content/Chapter-1-first-steps-in-programming/exercises-graphical-and-web-apps/sumator-web/sumator-web.md)
 * [2.1. Simple Calculations](Content/Chapter-2-1-simple-calculations/overview.md)
   * [The System Console](Content/Chapter-2-1-simple-calculations/system-console/system-console.md)