Introduction
Before getting into the detailed discussion of SD memory cards first I would like to discuss what SD memory cards are and why we use them. For the use of portable devices SD card association (SDA) introduced a new range of non-volatile digital storage devices named as SD memory cards.More than 8000 models of all 400 brands are using this SD memory card technology in their products. SD memory cards are now a day coming in three different sizes named as original, mini and micro. It is easy to hold larger cards by electrically passive adaptors which are already built in, in a host device.
History
A new version of devices provides compatibility with the older versions of SD memory cards while the older versions of devices do not provide compatibility to the newer versions of SD memory cards. There can be several types of SD memory cards identified by SDA. First is, micro SD memory cards and mini SD memory cards. Second is type, which includes those cards which contain more space for more busy users. Third categorization is of SD memory cards with input and output functions.
Features
Latter on further SD memory cards of higher storage capacity were introduced named as SDHC, SDSC and SDXC. The name of these cards is SDHC (Secure Digital High Capacity). They are able to store 16GB of data. They were introduced in 2.0 versions of SD memory cards. These are also compatible with any later versions of systems introduced. After SDHC, SDSC (Standard capacity SD cards) were introduced. The major issue after these cards was that devices which accept SDHC they also have to accept SDSC cards. After SDSC, SDXC were introduced. They are the abbreviation of Secure Digital Extended Capacity. These are really of higher capacity which has space of 2 TB.
Tips and comments
These cards have different features included in them. First very important feature that these cards support is the feature of security. These are only read only cards in order to prevent their data from changings that are made by any unknown or unauthenticated users in order to keep their documents safe and in original condition. In order to make memory cards ready only we can do it by the help of several commands. One of the simplest methods for this is to make your cards irreversible. Only error you will take due to this feature is in Microsoft windows. Error is that these windows require you to allow writing timestamps on your documents. So, you cannot put read only files in SD memory cards and switch them in your windows operating systems. However, if you had decided you will use only read only SD cards then you can make the feature of read only by looking at the top of the card where if the right side of the card is notched then the card is writing protected. If you see that card have no notch then that card is read and write protected we can read and write from that card at a time.
