why are some bearings cone shaped ?

ordering some bearings.
some look flat and some look cone shaped.
don't want to order the wrong ones.
can anyone explain?
or will the cone shaped ones look flat when fitted together?
thanks

https://www.rockauto.com/en/catalog/ford,1993,festiva,1.3l+l4,1128248,brake+&+wheel+hub,wheel+bearing,1672

Its a thrust style bearing. It will look like a "flat" one once installed.