the example memory card described herein utilizes one set of contacts and a signal protocol from one published memory card standard , such as that for the sd card , and the other set of contacts and a signal protocol according another published standard , such as the usb standard or another that provide similar opportunities for use , such as the ieee 1394 standard . many types of hosts include receptacle slots for sd cards , particularly cell phones , pdas , mp - 3 players , cameras and the like , while usb receptacles are common in personal computers , notebook computers and the like . such a combination of interfaces thereby allows the memory card system to be used directly with a wider variety of host devices than either one alone . referring to the figures , an example memory card will be described . a predominately rectangular main body portion 11 , in this case a shortened version of the sd card , has a rectangular extension 13 formed as part of the card to provide an additional interface , in this case a usb compatible plug . since the extension 13 is narrower than the portion 11 , end surfaces 12 and 14 of the main body portion 11 exist on either side of the extension 13 . according to the sd memory card specifications , nine electrical contacts 15 - 23 are provided on bottom surfaces of eight grooves 25 - 32 along one end of the card , the two contacts 22 and 23 being placed in the one groove 32 . four electrical contacts 37 - 40 , arranged according to the usb specifications , are provided on the flat surface of the extension 13 . both sets of contacts 15 - 23 and 37 - 40 are positioned on the same side of this example memory card but they could alternately be placed on opposite sides . in order to protect the contacts 37 - 40 when not being used , a cover 43 is rotatably connected with the card so that it may be closed to cover the contacts 37 - 40 when they are not being used ( the position of fig1 a , 2 a and 3 a ) and opened to expose the contacts 37 - 40 when the extension 13 is inserted into a matting receptacle ( the position of fig1 b , 2 b and 3 c ). these positions are shown to be one hundred eighty degrees apart . in this specific example , the cover 43 is attached to the card portion 11 at its end surfaces 12 and 14 by respective hinges 45 and 47 that allow for such rotation of the cover 43 by hand . the cover 43 has thick side portions 49 and 51 to which the hinges 45 and 47 are respectively connected . the side portions 49 and 51 fit around the extension 13 when the cover is closed , and a thin layer 53 of material spanning between the side portions 49 and 51 covers the contacts when the cover 43 is closed . the layer 53 has a size that is approximately that of the extension 13 in order to cover it when the cover 43 is closed . an end portion 55 spanning the side portions 49 and 51 is also preferably provided as part of the cover 43 . when the cover 43 is closed , its end portion 55 fits over an extreme end of the extension 13 . in order to be compatible with the usb specifications , the addition 13 has a minimum length of 12 mm . from the ends 12 and 14 of the main body portion 11 and has a width of 12 . 35 mm . the main body portion 11 of the memory card of fig1 a and 1b , in this specific example , is 24 mm . wide with a thickness of 2 . 1 mm ., according to the sd card standard , but its length is shortened so that the overall length of the card , with the cover 43 closed , is the 32 mm . length of the sd card . the cover 43 is made to have the same outside width of 24 mm . and its side portions 49 and 51 the same 2 . 1 mm . thickness as the card portion 11 , according to the sd card standard . the extension 13 has a thickness 43 of 1 . 70 mm . in the region of the contacts 37 - 40 , according to the usb specifications , which is less than the 2 . 1 mm . sd card thickness of the portion 11 . a 0 . 4 mm . high ledge may thus be formed at the intersection of the card portions 11 and 13 , given their different thicknesses , while an opposite surface on the backside of the first and second portions 11 and 13 is planar without any such discontinuity . the thickness difference on the front side is occupied by the layer 53 when the cover 43 is closed . the length of the cover 43 is such that the length of the card with the cover closed is the 32 mm . length of the sd card . therefore , when the cover 43 is closed , the card structure has the physical dimensions and other physical characteristics of the sd memory card . in order to hold the cover closed , a latch 57 may be provided on the inside of one or both of the side portions 49 and 51 of the cover 43 to snap into mating receptacle ( s ) ( not shown ) on the side walls of the extension 13 . when the cover 43 is closed , the card can be used as any sd card , the same as if the usb extension portion 13 did not exist . it is inserted into and removed from receptacles of host devices that follow the sd card standard . however , when it is desired to insert the card into a usb receptacle , the cover 43 is opened to expose the extension 13 and its contacts 37 - 40 . an appropriate latch ( not shown ) may additionally be included to hold the cover 43 in its opened position . in the example shown in the figures , the length of the extension 13 has been minimized according to the usb standards in order to maximize the length of the main body portion 11 so that it may hold more or larger integrated circuit chips . this results in the cover 43 , when in its opened position shown in fig1 b , not covering the contacts sd card contacts 25 - 32 . this is not a problem since the contacts 25 - 32 are included in grooves that minimize touching when being handled and are in any event normally so exposed in sd cards . however , if it is desired for the cover 43 to lie over the contacts 25 - 32 when opened , the length of the main portion 11 can be shortened and the extension 13 lengthened by a corresponding amount until they have about equal lengths . the length of the cover 43 would also then be increased in order to cover the lengthened extension 13 . when in its opened position , the cover would lie over the sd card contacts 15 - 23 . the extension 13 is illustrated in the figures to be centered along the width of the card portion 11 , the end edges 12 and 14 of the body portion 11 therefore being equal . however , other arrangements can be used instead . for example , the extension 13 can be positioned along one side of the portion 11 and the cover 43 altered to have one larger side portion instead of the two equal side portions 49 and 51 that are illustrated . various other details of the example structure shown in the figures can certainly be further altered so long as the contact structure at one end physically conforms to one standard and the contact structure at the other end physically conforms to a second standard . one is a memory card standard since numerous hand held devices include receptacles for such cards . a memory card standard other than for the sd card , such as one of the others described above , can be utilized instead . the second standard is one that is more commonly used on personal computers , notebook computers and other computing devices , in this case the usb standard . the ieee 1394 standard could instead be used for the second standard , for example , but its use is currently not as widespread as the usb . alternatively , both sets of contacts may conform to different memory card standards . internal to the memory card is preferably flash memory that is accessed from the sd card contacts 15 - 23 through a controller circuit , as currently exists in sd memory cards . an additional interface circuit is provided for converting the sd signal protocols at the sd contacts 15 - 23 into usb signal protocols at the usb contacts 37 - 40 . alternatively , a single controller can be used to provide both signal protocols . if one or more additional sets of contacts are provided , provision is made to interface the additional set ( s ) of contacts with the signal protocols of the additional standard ( s ), so that the internal memory can be accessed through the additional contact set ( s ). because of the two interfaces , the memory card of is useable with a wide variety of types of host devices . the sd card set of contacts 15 - 23 can be inserted into a memory card slot of a pda , for example , and the other set of contacts 37 - 40 into a usb receptacle of a notebook computer . addition of the second interface increases the convenience and portability of the memory card . this is an advantage for most all uses of memory cards but is of particular benefit in certain applications . for example , if the memory card stores the medical history and other health information of an individual who is carrying the card at the time of an accident or sudden illness , it is more likely that emergency health care providers will have access to a host device that can immediately read the stored information from the card through either of the two interfaces . the two interfaces also increase the usefulness of a memory card for transferring data between different types of hosts that do not have a common card interface . the second pattern of contacts and hinged protective cover of the card shown in the figures can be included in a memory card based upon most any standard memory card standard . this structure is not limited to use with the sd card . the usb plug 13 can , for example , be incorporated in a similar manner into the mmc , minisd , memory stick or smart media cards . the specific hinges 45 and 47 shown in the example memory card of the figures are sometimes called “ dog bone ” hinges . they are of rigid material . one end of each of these elongated hinges is attached to the card portion 11 to rotate about an axis 61 that extends across the width of the card through its main portion 11 . another end of each of the hinges 45 and 47 is attached to the cover 43 to rotate about an axis 63 that extends across the width of the cover 43 . both of the axes of rotation 61 and 63 are stationary with respect to their respective card portion 11 and cover 43 . during movement of the cover between its opened and closed positions , the axis 63 moves normal to the memory card to allow the cover 43 to adjust between the different levels of the card &# 39 ; s top surface . it will also be noted from the views of fig3 a - 3c that the mating edges of the cover 43 and main card portion 11 are curved to allow smooth motion between them as the cover 43 is moved by hand between its open and closed positions . the axis 63 also moves laterally along the length of the memory card as the cover is being opened or closed . this hinge structure can also be modified to provide a detent that holds the cover 43 in its closed position ( fig3 a ), in place of the latch 57 ( fig1 b ), and in its opened position ( fig3 c ). one way to do so is to square off the ends of the rigid hinges 45 and 47 and provide mating rectangular receptacles in the card portion 11 and cover 43 that latch the cover at 0 ° and 90 ° with respect to the hinges but allows free rotation between those positions . an alternate structure replaces the rounded edges of the card portion 11 and the cover 43 with substantially square surfaces , and the hinges 45 and 47 are provided some degree of elasticity so that they pull these planar edges together when the cover 43 is closed . as the cover is then opened by hand , the hinges stretch to allow the edge of the cover to rotate over the edge of the card portion 11 and then pull the cover and card together again after the cover has been rotated into its opened position . other alternatives to this specific hinge structure can certainly be used , so long as the cover 43 is rotatable by hand with respect to the card portions 11 and 13 about one or more axes extending across the width of the card . a different type of solid mechanical hinge can be used , for example . or something altogether different can be used . a flexible member adhered to the cover and the main card portion 11 , for example , may be substituted for the mechanical hinges . an example of the flexible member is polyimide film bonded or welded to the pieces . although the various aspects of the present invention have been described with respect to several exemplary embodiments and variations thereof , it will be understood that the invention is entitled to protection within the full scope of the appended claims .