Oracle

http://en.wikipedia.org/wiki/Oracle_Database

Closed source.

Often refered to by the version numbers, e.g. “Oracle 11g” or “Oracle 12g”.

Meaning of the letters I could find:

• i: internet
• g: grid
• c: cloud

Apparently those map to different architectures, whatever that means considering it’s closed source.

Default port: 1521 in older versions, 2843, 2844 in more recent ones.

XE

11g has a free version called Express Version (“EX”): http://www.oracle.com/technetwork/database/database-technologies/express-edition/overview/index.html with max 10GB storage, 1GB RAM and 1 core.