Is it possible to give a query in the from clause

Question

Hi all,

Is it possible to give a sql query in the from clause befor the giving a table name.
for instance:-

select top 1 Salary from(select top 2 Salary from  sstable order by Salary desc)  aas

 it is working but
my question is what is happening here

Whether a table is created  virtually in the name aas