diff --git a/docs/Windows.md b/docs/Windows.md
index 54e1330c91489..a73db3ab1fa26 100644
--- a/docs/Windows.md
+++ b/docs/Windows.md
@@ -4,7 +4,7 @@
 To be filled in.
 
 ## Windows Subsystem for Linux (WSL)
-- Note that all compiled Swift binaries are only executable within Bash on Windows and are Ubunutu, not Windows, executables.
+- Note that all compiled Swift binaries are only executable within Bash on Windows and are Ubuntu, not Windows, executables.
 - Make sure to run all commands from Bash, or the project won't compile.
 
 ###  1. Install WSL
diff --git a/include/swift/Syntax/RawSyntax.h b/include/swift/Syntax/RawSyntax.h
index ec3b290f87f92..ba45da8cbe59b 100644
--- a/include/swift/Syntax/RawSyntax.h
+++ b/include/swift/Syntax/RawSyntax.h
@@ -1,4 +1,4 @@
-//===--- Trivia.h - Swift Raw Syntax Nodes ----------------------*- C++ -*-===//
+//===--- RawSyntax.h - Swift Raw Syntax Nodes -------------------*- C++ -*-===//
 //
 // This source file is part of the Swift.org open source project
 //
diff --git a/include/swift/Syntax/Token.h b/include/swift/Syntax/Token.h
index 784227855fa7c..5174bc9ac8ee3 100644
--- a/include/swift/Syntax/Token.h
+++ b/include/swift/Syntax/Token.h
@@ -396,7 +396,7 @@ class Token  {
   /// Dump the structure of the raw syntax tree for debugging.
   void dump(llvm::raw_ostream &OS, unsigned Indent = 0) const;
 
-  /// Print the raw syntax tree with full formatting fideltiy.
+  /// Print the raw syntax tree with full formatting fidelity.
   void print(llvm::raw_ostream &OS) const;
 };
 
diff --git a/lib/Parse/Trivia.cpp b/lib/Parse/Trivia.cpp
index 74f89795c0aa7..109c549dcac34 100644
--- a/lib/Parse/Trivia.cpp
+++ b/lib/Parse/Trivia.cpp
@@ -1,4 +1,4 @@
-//===--- Lexer.h - Swift Source Trivia --------------------------*- C++ -*-===//
+//===--- Trivia.cpp - Swift Source Trivia ---------------------------------===//
 //
 // This source file is part of the Swift.org open source project
 //
diff --git a/lib/Sema/ConstraintSystem.h b/lib/Sema/ConstraintSystem.h
index 4700c92a0cefa..de23898fc6b38 100644
--- a/lib/Sema/ConstraintSystem.h
+++ b/lib/Sema/ConstraintSystem.h
@@ -2031,7 +2031,7 @@ class ConstraintSystem {
                                  ConstraintLocatorBuilder locator,
                                  bool isFavored);
 
-  /// \brief Collect the current inactive disjunciton constraints.
+  /// \brief Collect the current inactive disjunction constraints.
   void collectDisjunctions(SmallVectorImpl<Constraint *> &disjunctions);
 
   /// \brief Solve the system of constraints after it has already been
diff --git a/lib/Syntax/Token.cpp b/lib/Syntax/Token.cpp
index 27faeaa1a961b..f89befc9546b7 100644
--- a/lib/Syntax/Token.cpp
+++ b/lib/Syntax/Token.cpp
@@ -1,4 +1,4 @@
-//===--- Token.cpp - Token interface ----------------------------*- C++ -*-===//
+//===--- Token.cpp - Token interface --------------------------------------===//
 //
 // This source file is part of the Swift.org open source project
 //
@@ -88,7 +88,7 @@ void Token::dump(llvm::raw_ostream &OS, unsigned Indent) const {
   OS << ')';
 }
 
-/// Print the raw syntax tree with full formatting fideltiy.
+/// Print the raw syntax tree with full formatting fidelity.
 void Token::print(llvm::raw_ostream &OS) const {
   for (auto Leader : LeadingTrivia)
     Leader.print(OS);