NECKLETS: Necklets hang on the upper chest and don't commonly hang lower than the decollate.   Necklaces of this length are commonly worn against the skin of the chest rather than over top of clothing.

COLLARETTES: Collarettes are short necklaces that hang no longer than the collarbone and they typically have no dangles, tho we wouldn't want to rule them out ;).  Collarettes are not up against the throat like a choker, but are still pretty short, laying against the collarbone.  Necklaces of this length are also worn against the skin.

PENDANTS: A pendant is a "dangle" component suspended from a simple chain.  These can be any length, but many won't be any longer than the decollate.  Pendants are commonly worn both ways... either against the skin or over clothing.

LARIATS & LASSOS: A lariat necklace has a closed loop on one end and a weighted dangle on the other.  The weighted dangle goes through the loop to close the necklace.  No clasp is required.  A lasso necklace is very similar, but it generally has two weighted ends and ties or wraps, etc.  Again, these can be any length and are commonly worn against the skin or over clothing.

Y-NECKLACES: Y-Necklaces can be any length, but most commonly do not hang longer than the decollate.  They are commonly worn against the skin or over clothing.  This type of necklace generally closes in the front with a decorative clasp or toggle with a longish drop hanging from the clasp for a very attractive look.

NECKLACES: These are the full-blown necklaces that are most commonly worn over clothing.  They can hang generally anywhere on the chest and many exceed the breast line with some even reaching the navel.