SQL Server difference between catalog views, information schema views vs DMVs

I know information schema views are part of SQL standard, but I fin开发者_JAVA百科d catalog views as well as DMV "term" used interchangeably

any explanation that clearly tell us difference particularly difference between catalog views and DMV?

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Catalog views represent views over some hidden tables. They return data from the database itself (from disk).

DMVs represent views over internal functions. They return data from internal SQL structures (from memory). DMV names always start with sys.dm_.