I have a hard time keeping the various specifications from different cameras all straight. I know I don't really need to but sometimes it helps when reading a post to get a feel for where the poster is coming from or what they are talking about. I found it to be cumbersome to go to B&H or some other vendor and look them up and of course they don't have the older models.
I found that I can go to Wikipedia and put in a model , Canon 5D for instance,
and get all the specs very quickly.
At the bottom of a models page they have a Canon EOS time-line that has all the various EOS models linked. - VERY HANDY.
The sensor sizes are all put together here
as well.





