Files that are stored in Oracle ASM disk groups are called Oracle ASM files. Each Oracle ASM file is contained within a single Oracle ASM disk group. Oracle Database communicates with Oracle ASM in terms of files. This is similar to the way Oracle Database uses files on any file system. You can store the various file types in Oracle ASM disk groups, including:
Control files
Data files, temporary data files, and data file copies
SPFILEs
Online redo logs, archive logs, and Flashback logs
RMAN backups
Disaster recovery configurations
Change tracking bitmaps
Data Pump dumpsets
原文：http://www.cnblogs.com/claireyuancy/p/6710366.html