diff --git a/Source/cmFileCommand.cxx b/Source/cmFileCommand.cxx
index 9db8b85..8d20d35 100644
--- a/Source/cmFileCommand.cxx
+++ b/Source/cmFileCommand.cxx
@@ -2937,7 +2937,7 @@
   }
   fout.SetCopyIfDifferent(true);
 
-  // copy intput to output and expand variables from input at the same time
+  // copy input to output and expand variables from input at the same time
   std::stringstream sin(input, std::ios::in);
   std::string inLine;
   std::string outLine;