Oracle Database is the most popular RDBMS database developed by Oracle Corporation which is an object-relational database management system. This was written in Assembly language, C, C++. Oracle holds the top one position in the worldwide DBMS market share as per 2013.

Oracle have the main competitors of IBM, Microsoft, SAP, Teradata.

Oracle database is available in mainly 3 editions.

  1. Enterprise Edition
  2. Standard Edition
  3. Express Edition

Oracle Database server is a combination of Oracle Instance and Oracle Database.

Oracle Instance resides in the memory holding both Memory structures and the Background Processes.

Oracle Database will be on the storage (that would be the disk, sometimes ASM) which holds various files like datafiles, control files, redo log files, archive log files, SPfile, pfile , password files etc.