SQL = Structured Query Language
MS SQL Server = Database tool (like Oracle, or Access) on which SQL can be used to create, alter, update, and view data.
Simple answer. Oracle is a database. You can build it using SQL statements.
The current standard for SQL is SQL2, however everybody with implementations of Databases (Oracle, MS, etc) has a few syntactical querks... If you know SQL you can do a lot in Oracle with a little research into Oracle specific syntax.
Procedures, triggers, etc are another story.