Board Game Arena

I have played quite a few games always in "casual" mode. However I cannot figure out what the difference between "casual" and "competitor". I have never knowingly given or received assistance.

The casual lets you see the number of solitaire icons in your deck, it’s displayed right above your draw pile.
The competition mode doesn’t provide that info.

Also, in competition, during the drawing phase, you can’t see what the other players are drawing, until everybody has confirmed their draw.

Thanks.