What’s the difference tween mstdn.social and mastodon.social and can you switch servers if you wish?
@stephaniesheh mstdn.social is a Mastodon instance created by @stux.
mastodon.social is another instance of Mastodon, the "original" one.
You can find and follow from any Mastodon instance (so long as the instance you're on hasn't blocked an instance).
You could create an account on mastodon.social and point the one on mstdn.social to it, or vice versa using features in account settings. Or keep them separate.