INNODB provides MySQL with transaction security (acid-compatible) storage engine with Commit, rollback, and crash recovery capabilities. InnoDB locks the row level and also provides an oracle-consistent, unlocked read in the SELECT statement. These features add to multi-user deployment and performance. There is no need to enlarge the lock in InnoDB because the InnoDB row-level locking fits very small spaces. InnoDB also supports foreign key coercion. In SQL queries, you can freely mix innodb types of tables with other types of MySQL tables, even in the same query.
InnoDB is the maximum performance design for processing large amounts of data. Its CPU efficiency may be unmatched by any other disk-based relational database engine.
The InnoDB storage engine is fully consolidated with the MySQL server, and the InnoDB storage engine maintains its own buffer pool for caching data and indexes in main memory. InnoDB stores its tables & indexes in a tablespace, tablespaces can contain several files (or raw disk partitions). This is different from the MyISAM table, for example in the MyISAM table where each table is separated from the file. The InnoDB table can be any size, even on an operating system that has a file size limited to 2GB.
InnoDB is included in the MySQL binary distribution by default. Windows Essentials Installer makes InnoDB the default table for MySQL on Windows.
InnoDB is used in many large database sites that require high performance. The famous Internet news site slashdot.org runs on the InnoDB. Mytrix, Inc. stores more than 1TB of data on InnoDB, and some other sites handle an average of 800 inserts/updates per second on the InnoDB.