There are many different styles of settings. The function of the setting is to keep the diamonds securely in place and to attractively display them. There is a commonly held myth that you have to 'let light in' to diamonds by having an open style setting. If your diamond is well cut then it can be set in a solid block of metal and its brilliance will not be affected.
To decide on a setting type that will suit you, consider the styles that you find attractive, and also issues of practicality such as the height of the setting. If you are purchasing an engagement ring then also consider what type of wedding ring will sit next to it in the future.
Some diamonds rings cannot fit next to a classic round wedding ring, making it necessary to have a specially shaped wedding band. Other rings have the setting styled in such a way that a classic wedding ring sits beautifully.
Claw (also called prong) set designs minimize the visual presence of metal and maximize the display of the diamond, both in top view and side view. This style of setting is suited well to those who want to see very little metal, and to be able to see most of their diamond, including the edge or girdle of the stone.
Bezel set designs beautifully outline and emphasize the shape of a diamond. Bezel setting can also some times make your diamond look smaller than it is. It is very much personal taste and style that determine which setting is best for you.
The setting styles depicted below are channel set, claw set (or prong set), grain set (or bead set, or thread set), pavé set, hammer set 9 or gypsy set, or punch set, or flush set), bezel set, semi-bezel set, and a variety of claw set variations including corner-claw set for princess cut diamonds (corner-claw can also be used with trilliant cut diamonds or any diamond cut with sharp corners).