The shorter name for Secure digital cards is SD memory cards
. These are available in various capacities and have a specific slot on the device where they are to be inserted and used. But if you have 4gb sd memory cards, you can use them on the slots that are made for 1 gb cards. It is very easy to use 4 gb sd memory cards with pcs or cell phones or with cameras or with any other electronic device which requires memory cards. One needs to get 4gb sd memory cards when there are chances that one may require as lot of things to be saved in the memory.
When you want to use your 4gb sd memory cards with any of the devices, first check for the slot. That is seeing to it what kind of cards the slot supports. The two slots that are there for the SD cards are the SDHC slot and the SDIO slot. Now check the 4gb sd memory cards that you have. It is not that all the 4gb sd memory cards are supported by the same kind on slots. If the device you want to use for your 4gb sd memory cards does not any how support your card, then it can be upgraded.
With the slot for 1gb sd memory cards, empty the slot and put your 4 gb sd memory cards in the slot. Then move to the format option. If the device does not have this option, take support of the pc. From the icon My Computer you will be shown your card that has been attached. Then from here load a file into the drive and test your 4gb sd memory cards. If this allows the files to be opened it means that your cards are supported by the device.