Bridesmaid Prom

Bridesmaid Prom
What is the difference between the style of a prom dress and a bridesmaid dress (please continue to read)?

I get that prom dresses can sometimes be more than one color while bridesmaid's are usually a solid color with maybe a different color sash. Other than that, most prom dresses and most bridesmaid dresses look like they could be used for one occasion or the other. I just wondered if there was some guideline designers followed or is it just in the eye of the beholder?

Now a days, prom dresses are getting more crazier.

ex - shorter, brighter, more design, sequins, crystals

While bridesmaids or more simple and elagant

bridesmaids dresses are made to be more simple so the
bride stands out more.