Canon digital cameras have always been among the best in the industry and they continue to lead the market in unit sales. The Canon PowerShot SD300 Digital ELPH is the least expensive of the three digital cameras that shares the housing the SD300 uses. If you're willing to spend more or require more resolutions than the 4 Megapixel the SD300 provides, you can test out the SD400 (5 Megapixel) and SD500 (7.1 Megapixel). Aside from higher resolution, there's really not much differences between the three cameras. The SD in this case stands for Secure Digital, the media the SD300 uses for memory. It is the use of SD media that Canon was able to make this PowerShot so small.