Bigger than a house floating in the sky.I know what,I saw, but don't know why!

Sunny day with a few , what I call marshmello clouds, I looked up to enjoy the   beutiful clouds,when all of a sudden a large,round saucer come out from behind        a .cloud.  Larger than a football field   There was no sound at all. Silver or white   it reminded me of what the hills must have seen. the flat side was toward the ground,and it just sat  there,like it was waiting for me to do something.  I wasn't scared, just     wondered what it was going to do, come down or go up.  Finally, it went straight up.  Flat like a pancake, then as come another cloud it tilted edge wise and went into the cloud,that was higher than the one it came out of.  I presume so it would not      disturb the cloud. I don't know why I saw it,maybe they wanted me to know they are here.    I just got a computer or I would have reported it sooner.
Date is approximate.  PD