When you create a user, using the CREATE USER command in SQL*Plus or an equivalent command in Enterprise Manager, Oracle creates a schema. There is a CREATE SCHEMA command in SQL*Plus, but it does not actually create a schema; the CREATE SCHEMA command just loads objects into an existing schema. The only way to create a schema is therefore to create a user with the CREATE USER command.
There is one type of schema, but there are many types of users, which I know sounds confusing since schemas are supposed to be users. If you are using Oracle Internet Directory then you can create Oracle database users that have no schema, as one example of this dichotomy.
Probably what you wanted to know is, are there different types of users like developers, administrators, etc. By default all users are created equal, and they have zero abilities in Oracle. After you create the user you must grant privileges and/or roles (a role is a group of privileges) to the new user. To make user BOB a developer you might "grant create session, resource to BOB". To make BOB an administrator you might "grant create session, dba to BOB".