PL/SQL is developed by Oracle Corporation to increase/enhance capabilities of SQL, PL/SQL stands for Procedural Language extension to SQL . PL/SQL is highly structured and expressive language and because of its expressive syntax it is very easy to understand and learn
PL/SQL is integrated with Oracle Database and can be called from any other programming language. It is tightly integrated with SQL so it's easy to learn PL/SQL if you have knowledge of SQL