diff --git a/format.h b/format.h
index 15c522f9..a9fdfdbd 100644
--- a/format.h
+++ b/format.h
@@ -603,8 +603,8 @@ void Buffer<T>::append(const U *begin, const U *end) {
 
 namespace internal {
 
-// A memory buffer for POD types with the first SIZE elements stored in
-// the object itself.
+// A memory buffer for trivially copyable/constructible types with the first SIZE
+// elements stored in the object itself.
 template <typename T, std::size_t SIZE, typename Allocator = std::allocator<T> >
 class MemoryBuffer : private Allocator, public Buffer<T> {
  private:
@@ -949,8 +949,8 @@ struct Value {
   };
 };
 
-// A formatting argument. It is a POD type to allow storage in
-// internal::MemoryBuffer.
+// A formatting argument. It is a trivially copyable/constructible type to
+// allow storage in internal::MemoryBuffer.
 struct Arg : Value {
   Type type;
 };