Basic Connector Terminology

Connectors are used to join subsections of prineted circuit boards together. Usually, a connector is used where it may be desirable to disconnect the subsections at some future time: power inputs, peripheral connections, or boards which may need to be replaced.

Mating cycles: Connectors have a finite life, and connecting and disconnecting them frequently can wear them out quickly. A USB connector may have a lifetime in the thousands or tens of thousands of cycles, while a board-to-board connector designed for use inside of consumer electronics may be limited to tens of cycles. It’s important that you select a connector with a suitable life for your application.

Mount: This one has the potential for being confusing. The term “mount” can refer to several things: how the connector is mounted in use (panel mount, free-hanging, board mount), what the angle of the connector is relative to its attachment (straight or right-angle), or how it is mechanically attached (solder tab, surface mount, through hole). 

Strain relief: When a connector mounts to a board or cable, the electrical connections tend to be somewhat fragile. It is typical to provide some kind of strain relief to transfer any forces acting on that connector to a more mechanically sound object than the fragile electrical connections.
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