the real name of sharepoint 2010 and exchange which is installed on sbs2011 and can you this products install freely on essential version of microsoft

hello,

I see that sharepoint 2010 is installed on sbs 2011 standaard , but this product of sharepoint which version is ? I mean version 3 or 4 .  the same question I ask for exchange.

my second question is can you this products install freely on essential version of sbs.

thanks

johan

h.david