Information about storge engine in PostgreSQL

Hello

MySQL has information about several storage engines. MEMORY to handle
temporary tables, InnoDB to handle transactions and which also can split
its table data over several files/partitions. Splitting of storage is
something which according to the following article, PostgreSQL does not
support:

http://www.devx.com/dbzone/Article/20743

But I cannot verify this due to lack of information. I haven't found any
similar information about the storage engine used by PostgreSQL which I
think is called Postgres.

Do you know of any places where this information can be obtained?

Thank you.