I know information schema views are part of SQL standard, but I find catalog views as well as DMV "term" used interchangeably
any explanation that clearly tell us difference particularly difference between catalog views and DMV?
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_.