A hex bit socket is a specially designed bit that fits into a manual or power screwdriver or drill. Such sockets are usually two-sided, with one side featuring the male, or driver, unit and the other side featuring the female, or socket, unit. Both the male and female ends are made to work with fasteners that have six sides.
The word "hex" is derived from the Greek hexa, which means six. The male end of a hex bit socket is made specifically for screws that have hexagonal holes in the top rather than the more-frequently seen flat slot or set of crossed slots. The male end, which is usually a small six-sided rod, is inserted into the hole in the screw and then turned to either drive the screw or reverse it out. Such screws are less prone to stripping than screws with traditional heads, making them easier to screw into resistant materials. In addition, hex-head screws are far more difficult to remove without the proper tool, unlike traditional screws, which can often be removed using a knife or other thin, flat, sturdy object.
The female end of a hex bit socket is simply a cuff of metal into which a deep six-sided depression has been formed. This opening is made to receive a six-sided piece of hardware, usually a nut. The socket goes over the nut, making contact on all sides. As the socket is turned, the nut loosens or tightens, depending on the direction of torque.
The term "bit," when used in relation to tools, refers to a specially made attachment that is designed to be inserted into a screwdriver or drill head. Bits can be changed out according to need, eliminating the need for several tool bodies. Manual and powered screwdrivers, as well as power drills, are designed to accept such bits. Drill bits are usually universal, meaning that they can be used with any drill on the market, but bits made for manual drivers may be incompatible with powered drivers and vice versa.
Bits, including hex bits, are available in a wide variety of standard sizes, which correspond to the standard sizes of the hardware they are meant to engage. Those looking to purchase a hex bit socket might opt to buy an individual bit in the size that matches their needs. These bits, however, are also sold in hex bit socket kits or sets, which may contain as few as three and as many as 20 or more sockets in differing sizes.