This is Part 3 of a series of quick learning guides for Oracle designers, developers and managers. Part 3 introduces new entrants to the main concepts of the SQL language and to the use and development of Oracle's PL/SQL procedural version of SQL. The guide includes details of how to install and use a SQL*Plus client and the basic use of Oracle's SQL Developer tool. The guide also provides a foundation in coding practise in SQL and PL/SQL with some basic guidelines for good practise in coding and managing SQL and PL/SQL software performance issues. These guides are designed to rapidly deliver key information about Oracle to the following audience groups: Project Managers, Team Leaders, Analysts, Designers, Developers and Testers who are new to Oracle and need rapid access to strategic information about the Oracle development environment.