1. Fixed Block File
2. Fixed Unblock File
3. Variable Block File
4. Variable Unblock File
5. Printer File

Following are the explanation to the POINTS one by one:

1. Fixed Block File: We can identify that a file is a fixed block file if the following 3 conditions are met:
   • ORGANIZATION IS SEQUENTIAL
   • RECORDING MODE IS F
   • BLOCK CONTAINS 0
2. Fixed Unblock File: We can identify that a file is a fixed unblock file if the following 2 conditions are met:
   • ORGANIZATION IS SEQUENTIAL
   • RECORDING MODE IS F
3. Variable Block File: We can identify that a file is a variable block file if the following 4 conditions are met:
   • ORGANIZATION IS SEQUENTIAL
   • RECORDING MODE IS V
   • BLOCK CONTAINS 0
   • Record length is never CODED as 4 bytes in FD as JCL will consider the record length as the max length of record plus 4.
4. Variable Unblock File: We can identify that a file is a variable unblock file if the following 3 conditions are met:
   • ORGANIZATION IS SEQUENTIAL
   • RECORDING MODE IS V
   • Record length is never coded as 4 bytes in FD as JCL will consider the record length as the max length of record plus 4.
5. Printer File: We can reference that a file is a printer file if the following 3 conditions are met:
   • ORGANIZATION IS SEQUENTIAL
   • RECORDING MODE IS F
   • BLOCK CONTAIN 0