What does it mean that there are several D's on the back of Canon camera?

D means number, which means number. Canon's SLR cameras are all named after XXXD.

Canon cameras are generally divided into the following levels:

Entry-level, D is preceded by three digits and four digits, such as 1000D, 100D, 760D, etc.

In the intermediate stage, there are two digits before d, such as 50D, 60D, 70D, etc.

Professional grade, with only one digit before d, such as 1D, 5D, 7D, etc.

Generally speaking, the larger the number, the newer the performance of the model with the same number of digits, such as Canon 450D, 500D and 550D.

Extended data:

EOS series adopts Quan Huafu CMOS image sensor independently developed and produced by Canon, and its size is the same as that of traditional 35mm film. It can perfectly cooperate with Canon's prestigious EF lens group and bring high-quality photos beyond imagination to professional photographers.

Thanks to the high-performance DIGIC III which can be processed simultaneously and in parallel, the image processing speed of the camera is four times that of EOS- 1D Mark II N, and the powerful processing performance greatly increases the maximum number of shots of the camera. Making it possible to play back images while data is written into the memory card; Automatic white balance is also more accurate.

The camera's dual "DIGIC III" processing system supports 14-bit analog/digital signal conversion, and supports a larger cache, so that data can be written into the memory card faster and the cache can be emptied faster. At the same time, the compression speed of JPEG images is greatly improved, which makes the real-time display very smooth with a frame rate of about 30 frames/second when the shooting mode is displayed in real time.

Baidu Encyclopedia-Canon Digital Camera