What is the difference between MBA/PGDM and PGDBM/PGDBA ?

Both MBA/MMS/PGDM and PGDBM/PGDBA are postgraduate programs offered in management studies and are used to connote the same thing. An MBA/MMS is usually a degree program that is offered by a university, ata the same time PGDM/PGDBM/PGDBA is a postgraduate diploma offered by autonomous B-Schools/Institutes. The denomination hardly makes any difference  in the program as long as the program is recognized by a competent authority like University under the Central/State Legislature, Deemed University, Institutes approved by the Ministry of HRD and the AICTE.