Identification
The SD card slot is found on the front of the Wii, under a white panel. It will appear as a vertical line that is a few centimeters thick.
Significance
One of the earliest complaints about the Wii was its limited storage space. The SD card slot solves this problem by expanding storage by up to 32GB.
Time Frame
The Wii SD card slot could be used for external storage of saved games from the initial ship date. In March 2009, Nintendo released a firmware update to allow for storage of games, channels and other files and the use of SDHC cards.
Benefits
By using the SD card slot, users can download or purchase more content from the Wii Internet channel, without needing to delete existing files.
Considerations
As of Wii Menu 4.0, SD cards less than 2GB and SDHC cards less than 32GB are supported. Cards above this threshold are not supported.