* Drive Size: The drive size of a socket is just that, the size of the fitting. The 1/4" is the last size and the smallest and great for squeezing into tight spots. It's also handy with woodwork and smaller home repair.
* Depth: Sockets come in two different depth sizes, standard and deep. Deep drive sockets are able to turn nuts that have bolts that are extended. Standard sockets would not be able to reach these nuts.
* Number of Points: are made but are rare, and are designed for square nuts with four or eight sides.
