diff --git a/src/backends/maxima/maximaexpression.cpp b/src/backends/maxima/maximaexpression.cpp
--- a/src/backends/maxima/maximaexpression.cpp
+++ b/src/backends/maxima/maximaexpression.cpp
@@ -401,7 +401,7 @@
     }
     else
     {
-        //no latex output is availabe, the actual result is part of the textContent string
+        //no latex output is available, the actual result is part of the textContent string
         result = new Cantor::TextResult(textContent);
     }
 
diff --git a/src/backends/maxima/testmaxima.h b/src/backends/maxima/testmaxima.h
--- a/src/backends/maxima/testmaxima.h
+++ b/src/backends/maxima/testmaxima.h
@@ -37,7 +37,7 @@
     void testSimpleCommand();
     //tests a command, containing more than 1 line
     void testMultilineCommand();
-    //tests if the command queue works correcly
+    //tests if the command queue works correctly
     void testCommandQueue();
     //tests doing a plot
     void testPlot();
diff --git a/src/backends/octave/octavesession.cpp b/src/backends/octave/octavesession.cpp
--- a/src/backends/octave/octavesession.cpp
+++ b/src/backends/octave/octavesession.cpp
@@ -286,7 +286,7 @@
             // octave print subprompt and waits input finish.
             m_syntaxError = true;
             qDebug() << "subprompt catch";
-            m_process->write(")]'\"\n"); // forse exit from subprompt
+            m_process->write(")]'\"\n"); // force exit from subprompt
             m_output.clear();
         }
         else
diff --git a/src/backends/octave/testoctave.h b/src/backends/octave/testoctave.h
--- a/src/backends/octave/testoctave.h
+++ b/src/backends/octave/testoctave.h
@@ -37,7 +37,7 @@
     void testSimpleCommand();
     //tests a command, containing more than 1 line
     void testMultilineCommand();
-    //tests if the command queue works correcly
+    //tests if the command queue works correctly
     void testCommandQueue();
 
     void testVariableDefinition();
diff --git a/src/cantor.cpp b/src/cantor.cpp
--- a/src/cantor.cpp
+++ b/src/cantor.cpp
@@ -278,7 +278,7 @@
         int backendListSize = 0;
         foreach(Cantor::Backend* b, Cantor::Backend::availableBackends())
         {
-            if(!b->requirementsFullfilled()) //It's disabled because of misssing dependencies, not because of some other reason(like eg. nullbackend)
+            if(!b->requirementsFullfilled()) //It's disabled because of missing dependencies, not because of some other reason(like eg. nullbackend)
             {
                 backendList+=QString::fromLatin1("<li>%1: <a href=\"%2\">%2</a></li>").arg(b->name(), b->url());
                 ++backendListSize;
diff --git a/src/lib/backend.h b/src/lib/backend.h
--- a/src/lib/backend.h
+++ b/src/lib/backend.h
@@ -143,16 +143,16 @@
     /**
      * Returns an Url pointing to the Help of the Backend
      * The method should be overwritten by all Backends(who have an online help)
-     * You should make the returned Url translateble, e.g. by doing something like:
+     * You should make the returned Url translatable, e.g. by doing something like:
      * return i18nc("the url to the documentation of KAlgebra, please check if there is a translated version and use the correct url",
      *   "http://docs.kde.org/stable/en/kdeedu/kalgebra/");
      * @return Url of the help
      */
     virtual QUrl helpUrl() const;
     /**
      * Returns if the backend should be enabled (shown in the Backend dialog)
      * @return @c true, if the enabled flag is set to true, and the requirements are fulfilled
-     * @return @c false, if the backend was purposly disabled, or requirements are missing
+     * @return @c false, if the backend was purposely disabled, or requirements are missing
      * @see requirementsFullfilled()
      */
     bool isEnabled() const;
diff --git a/src/lib/session.h b/src/lib/session.h
--- a/src/lib/session.h
+++ b/src/lib/session.h
@@ -235,7 +235,7 @@
     virtual void finishFirstExpression(bool setDoneAfterUpdate = false);
 
     /**
-     * Starts variable update immideatly, useful for subclasses, which run internal command
+     * Starts variable update immedeatly, useful for subclasses, which run internal command
      * which could change variables listen
      */
     virtual void updateVariables();
diff --git a/src/loadedexpression.cpp b/src/loadedexpression.cpp
--- a/src/loadedexpression.cpp
+++ b/src/loadedexpression.cpp
@@ -260,7 +260,7 @@
             }
             else if (mainKey == Cantor::JupyterUtils::latexMime)
             {
-                // Some latex results contains alreadey rendered images, so use them, if presents
+                // Some latex results contains already rendered images, so use them, if presents
                 const QImage& image = Cantor::JupyterUtils::loadImage(data, Cantor::JupyterUtils::pngMime);
 
                 QString latex = Cantor::JupyterUtils::fromJupyterMultiline(data.value(mainKey));
diff --git a/src/markdownentry.cpp b/src/markdownentry.cpp
--- a/src/markdownentry.cpp
+++ b/src/markdownentry.cpp
@@ -589,7 +589,7 @@
     {
         m_textItem->document()->addResource(QTextDocument::ImageResource, internal, QVariant(image));
 
-        // Dont add new line for $$...$$ on document's begin and end
+        // Don't add new line for $$...$$ on document's begin and end
         // And if we in block, which haven't non-space characters except out math expression
         // In another sitation, Cantor will move rendered image into another QTextBlock
         QTextCursor prevSymCursor = m_textItem->document()->find(QRegExp(QLatin1String("[^\\s]")), cursor, QTextDocument::FindBackward);
diff --git a/src/mathrender.h b/src/mathrender.h
--- a/src/mathrender.h
+++ b/src/mathrender.h
@@ -27,7 +27,7 @@
 #include "lib/latexrenderer.h"
 
 /**
- * Special class for renderning embedded math in MarkdownEntry and TextEntry
+ * Special class for rendering embedded math in MarkdownEntry and TextEntry
  * Instead of LatexRenderer+EpsRenderer provide all needed functianality in one class
  * Even if we add some speed optimization in future, API of the class probably won't change
  */
diff --git a/src/mathrendertask.cpp b/src/mathrendertask.cpp
--- a/src/mathrendertask.cpp
+++ b/src/mathrendertask.cpp
@@ -165,7 +165,7 @@
         result->errorMessage = renderErrorText;
 
         finalize(result);
-        texFile.setAutoRemove(false); //Usefull for debug
+        texFile.setAutoRemove(false); //Useful for debug
         return;
     }
 
diff --git a/src/textentry.cpp b/src/textentry.cpp
--- a/src/textentry.cpp
+++ b/src/textentry.cpp
@@ -59,7 +59,7 @@
     connect(m_textItem, &WorksheetTextItem::doubleClick, this, &TextEntry::resolveImagesAtCursor);
 
     // Init raw cell target menus
-    // This used only for raw cells, but removing and creating this on convertation more complex
+    // This used only for raw cells, but removing and creating this on conversion more complex
     // that just create them always
     m_targetActionGroup= new QActionGroup(this);
 	m_targetActionGroup->setExclusive(true);
@@ -223,7 +223,7 @@
 {
     // Simple logic:
     // If convertTarget is empty, it's user maded cell and we convert it to a markdown
-    // If convertTarget setted, it's raw cell from Jupyter and we convert it to Jupyter cell
+    // If convertTarget set, it's raw cell from Jupyter and we convert it to Jupyter cell
 
     QTextDocument* doc = m_textItem->document()->clone();
     QTextCursor cursor = doc->find(QString(QChar::ObjectReplacementCharacter));
diff --git a/src/worksheet.h b/src/worksheet.h
--- a/src/worksheet.h
+++ b/src/worksheet.h
@@ -113,7 +113,7 @@
      * 1. WorksheetView -> Worksheet -> subelemenets (ex. entries) about view width
      *   View width used by some sub elements for better visual appearance (for example, entries with text often are fitted to width of view).
      * 2. Subelements -> Worksheet
-     *   Sub elements notify Worksheet about their needed widths and worksheet, used this information, set propper scene size.
+     *   Sub elements notify Worksheet about their needed widths and worksheet, used this information, set proper scene size.
      */
     /// First information stream
     void setViewSize(qreal w, qreal h, qreal s, bool forceUpdate = false);
diff --git a/src/worksheet.cpp b/src/worksheet.cpp
--- a/src/worksheet.cpp
+++ b/src/worksheet.cpp
@@ -1209,7 +1209,7 @@
     delete m_session;
     m_session=nullptr;
 
-    //file can only be loaded in a worksheet that was not eidted/modified yet (s.a. CantorShell::load())
+    //file can only be loaded in a worksheet that was not edited/modified yet (s.a. CantorShell::load())
     //in this case on the default "first entry" is available -> delete it.
     if (m_firstEntry) {
         delete m_firstEntry;
@@ -1286,7 +1286,7 @@
     int nbformatMajor, nbformatMinor;
     if (!Cantor::JupyterUtils::isJupyterNotebook(doc))
     {
-        // Two possiblities: old jupyter notebook (version <= 4.0.0 and a another scheme) or just not a notebook at all
+        // Two possibilities: old jupyter notebook (version <= 4.0.0 and a another scheme) or just not a notebook at all
         std::tie(nbformatMajor, nbformatMinor) = Cantor::JupyterUtils::getNbformatVersion(doc.object());
         if (nbformatMajor == 0 && nbformatMinor == 0)
         {