Schemas

Oracle database conventions refer to defined groups of ownership (generally associated with a "username") as schemas.
Most Oracle database installations traditionally come with a default schema called SCOTT. After the installation process has set up the sample tables, the user can log into the database with the username scott and the password tiger

. (The name of the SCOTT schema originated with Bruce Scott, one of the first employees at Oracle (then Software Development Laboratories), who had a cat named Tiger.)
The scott schema has fallen out of favor as it uses so few of the features of a modern release of oracle. Most recent examples reference the default hr or oe schema.

Other default schemas include: 

• SYS (essential core database structures and utilities)

• SYSTEM (additional core database structures and utilities, and privileged account)

• OUTLN (utilized to store metadata for stored outlines for query optimizer plan stability.

• BI, IX, HR, OE, PM, and SH (expanded sample schemasSCOTT