Vowel whose quality does not change over the duration of the vowel is called a monophthong. Monophthongs are sometimes called "pure" or "stable" vowels. A vowel sound that glides from one quality to another is called a diphthong, and a vowel sound that glides successively through three qualities is a triphthong. All languages have monophthongs and many languages have diphthongs, but triphthongs or vowel sounds with even more target qualities are relatively rare cross-linguistically. English has all three types: the vowel sound in "hit" is a monophthong , the vowel sound in "boy" is in most dialects a diphthong , and
Blittable types The following are some commonly used non-blittable types in the .NET framework: There are many more blittable and non-blittable types, and user-defined types may fit in either category depending on how they are defined (MSDN). This very restrictive notion of blittable types appears to limit the usefulness of the interoperability services provided by .NET, but this is not so. While blittable types allow a straightforward definition of interoperable types, various ways exist to explicitly define how a non-blittable type should be converted by the interop marshaler. For example, in the .NET languages there are many attributes which can be applied