Electrical connectors are used to electrically connect one component to another component. Depending upon the particular application, an electrical connector may be required to satisfy certain criteria, such as, contact resistance, compliance or deflection distance, force required to achieve compliance, ease of assembly, and cost to manufacture. A typical electrical connector includes some form of insulating or dielectric housing having an opening or receptacle for receiving a complementary mating connector or other mating connecting device. The housing may be molded of plastic material, and the terminals may be stamped and formed of sheet metal material. The connector housing typically has a front mating end and a rear termination end. Each terminal includes a front contact end and a rear terminating end. A plurality of conductive terminals have contact portions exposed at or in the receptacle for engaging appropriate contacts of the mating connector. The wire is inserted or forced into the contacts to provide electrical connection. The plastic housing provides structural support for the contacts. A backshell is often used on an electrical connector to protect the conductors of the electrical cable which are connected to the contacts in the connector. The backshell prevents dust, particles and moisture from entering the rear of the connector. Other protectible components also may be exposed in the receptacle. The housing may include a mating end for interengaging a mating connector or other complementary connecting device. The terminals of electrical connectors frequently are very small components, such as components that are stamped and/or formed from thin sheet metal material. When the connector is mated with the mating device or second connector, some form of latching means often is provided to prevent the connectors from becoming unintentionally unmated. Electrical connectors and couplings are usually made of metal, or include metal components, in order to provide strength and electrical conduction properties. A terminal position assurance (TPA) member may be used to assure reliable engagement of the terminals with a housing of the connector. The TPA secures terminal contacts within respective contact cavities in the connector. The TPA secures the terminal contact in proper position for electrically mating with the terminal contacts of a mating connector or other electrical component. Electrical connectors are conventionally formed of male terminals (plugs) and female terminals (sockets) so that the plugs are inserted either coaxially or at some small angle into respective sockets. The plugs and sockets generally have circular cross sections and engage coaxially. Electrical connection systems to date have generally included molded male plugs having two to three electrical elements, typically having at least two blades. These plugs connect to corresponding two and three element female connectors and carry electricity to various devices. Plug and jack type connectors are well known for use in connecting electrical equipments. A plug connector generally comprises a plug pin. A widely used type of electrical connector receptacle commonly is referred to as a jack. A jack connector generally comprises a dielectric housing having a front mating end with a plug-receiving opening.

Electrical connectors are provided in many different varieties for numerous applications. A wide variety of connectors exist for various applications. In the automotive industry, electrical connectors may be used within instrument panels of a vehicle interior panel. Electrical connectors and joints allow electrical communication between systems such as a power source and a time display. Electrical connectors can be used to connect electrical equipment, such as transformers, to high-voltage power distribution networks. Modular electrical connectors are often used to establish electrical contact between electrical as components such as backplanes, motherboards, daughter cards, etc. Zero insertion force (ZIF) electrical connectors are used for electrically connecting electronic packages such as central processing units (CPUs) with circuit substrates such as printed circuit boards (PCBs). Quick disconnect connectors are in widespread use in many industrial applications, such as manufacturing automation. Land grid array (LGA) electrical connectors are widely used in the connector industry for electrically connecting CPU chips to PCBs. Board-to-board electrical connector assemblies are widely used and applied in all kinds of electrical equipments to electrically connect two separate PCBs. Card edge connectors are widely used to connect daughter cards and mother boards. Mezzanine-type electrical connectors are typically used to electrically couple a first and a second circuit substrate. Crimp connectors are commonly used for establishing an electrical connection between the ends of two electrical conductors. Audio jack connector is widely used in the electric industry for providing audio signals transmission between two electrical equipments. Electrical plug connectors are utilized in large numbers in electrical appliances of the consumer goods industry, such as for example large and small domestic appliances. Electrical card connectors, such as PCMCIA card connectors, are widely used in computer industry for electrically connecting with inserted electronic cards which function as removable mass storage devices. Sealed electrical connectors are used in many areas, such as in the automotive industry and in outdoors commercial fields, to protect electrical connections from moisture or other contaminants. In today's vehicles, there are many systems, particularly vehicle safety and control systems, such as brake or wheel speed sensors, exterior lighting assemblies, fuel injector connections, and other engine compartment applications that utilize electrical connectors in environments where it is desirable to protect the internal contacts of the connector from contamination. Sealed connectors or waterproof connectors are commonly used to provide electrical connections in applications requiring a high degree of water resistance, such as in automobile wiring harnesses, appliances, underwater cameras, and other consumer devices.

Various structures of a connector are used for obtaining a removable electrical connector to connect removably to the mating connector. Modular electrical connectors used in applications of this type often comprise a plug, and a receptacle for mating with the plug. The plug and the receptacle may each comprise a plurality of printed circuit boards having conductive traces formed thereon. A typical lever type electrical connector assembly includes a first connector which has an actuating or mating assist lever rotatably mounted thereon for connecting and disconnecting the connector with a complementary mating second connector. Loadbreak connectors used in conjunction with 15 and 25 KV switchgear generally include a power cable elbow connector having one end adapted for receiving a power cable and another end adapted for receiving a loadbreak bushing insert. A ZIF electrical connector comprises a base soldered to and electrically connected with a PCB, a cover slideably mounted on the base and having a CPU attached thereon, and an actuating device for actuating the cover to slide along the base. Waterproof connectors typically house one or more terminals secured to one or more terminal wire ends. A waterproof connector may be a male connector or a female connector, although female waterproof connectors are more common. Board-to-board connector assembly generally includes two matable connectors respectively mounted on two parallelly spaced printed circuit boards (PCB) to electrically connect these two PCBs for signal transmission therebetween. A mezzanine-type connector comprises a plug for mounting on the first circuit substrate, and a receptacle for mounting on the second circuit substrate. The plug comprises a plurality of contacts that each engage a corresponding contact on the receptacle when the plug and the receptacle are mated, thereby establishing electrical contact between the first and second circuit substrates. A LGA electrical connector comprises an insulative housing, a multiplicity of terminals received in the housing in a rectangular array, a metal load plate pivotally mounted to the housing, and a load lever attached to the housing. A multi-bladed electrical connector has a male connector portion which firmly supports a series of male terminals that are locked within respective terminal cavities of the male connector portion. A female connector portion of the electrical connector mates typically via a snap locking feature to the male connector portion. Ball grid array connectors typically use solder portions known as solder balls on the ends of contact elements. A typical crimp connector comprises a malleable metallic crimp barrel surrounded by a heat-shrinkable sleeve, with a layer of heat-activated adhesive being applied to the inner surface of the sleeve. Typically, each of the card edge connectors generally comprises an elongate housing defining an elongate slot for receiving a mating edge of the daughter card, a plurality of terminals are spaced along one or both sides of the slot for engaging conductive pads disposed on the mating edge of the daughter card, and a pair of latch members attached to opposite ends of the housing. A high density electrical connector generally has a very large number of electrical contacts and very small contact pitch for large data storage capacity and high transfer rates.

Connectors are in widespread use in the electronics industry. In the computer and microelectronics industry, electrical connectors may be provided in two separate portions designed to mate with each other. Various electronic systems comprise a wide array of components mounted on printed circuit boards, such as daughterboards and motherboards, which are interconnected to transfer signals and power throughout the system. The transfer of signals and power between the circuit boards requires electrical interconnection between the circuit boards. Electrical connectors are widely used in personal computer systems to electrically connect a plurality of wires for carrying high currents with a mating electrical connector mounted on a printed circuit board (PCB).  Various types of electrical connectors are designed for mounting on a printed circuit board. The connectors typically have sockets to receive the electrical cards therein and headers connected to the computer device such that data can be transferred therebetween. Card edge connectors are widely used to connect daughter cards and mother boards. A board mounted connector includes some form of dielectric housing which mounts one or more conductive terminals. The terminals have terminating ends for connection to appropriate circuit traces on the board and contact ends on or in the housing for engagement with appropriate contacts or terminals of a complementary mating connector.  Flexible printed circuit (FPC) connectors are widely used for electrically connecting flexible printed circuits to PCBs. A flexible printed circuit connector comprises an insulating housing, a plurality of electrical contacts received in the insulating housing and an actuator mounted movably on the insulating housing. A typical CPU socket comprises a base soldered and electrically connected with the PCB, a cover slidably attached on the base and having a CPU, and an actuation device assembled between the base and the cover for actuating the cover to slide along the base. A variety of board-to-board electrical connectors to electrically interconnect two boards or equivalent have been developed. The board-to-board electrical connector has a pair of male and female connectors each having one or more contacts.