IEFBR14 can be used to catalog the datasets. The dataset can be either Sequential file(PS) or Partitioned Dataset(PDS). To catalog the dataset, the disposition should be DISP=(OLD,CATLG,..). CATLG will do two tasks -

1. Creates entry in system or user catalog directory for dataset.
2. All needed indexes will be created.

//Job Card
//*
//STEP1    EXEC PGM=IEFBR14
//SYSPRINT DD SYSOUT=*
//SYSOUT   DD SYSOUT=*
//SYSDUMP  DD SYSOUT=*
//DD1      DD DSN=datset.name, DISP=(OLD,CATLG,..)

Below example to catalog the PS and PDS using IEFBR14 utility which are uncataloged earlier.

----+----1----+----2---+---3----+---4---+---5---+---6----+---7--
***************************** Top of Data ***************************
//MTHUSRD  JOB (123),'MTHUSR',CLASS=A,MSGCLASS=A,MSGLEVEL=(1,1),
//             NOTIFY=&SYSUID                   
//************************************************************* 
//* CATALOG DATA SET USING IEFBR14 UTILITY          
//*************************************************************
//STEP01   EXEC PGM=IEFBR14                     
//SYSPRINT DD SYSOUT=*                 
//SYSOUT   DD SYSOUT=*              
//SYSDUMP  DD SYSOUT=*                 
//DD1      DD DSN=MTHUSR.TEST.PSFILE,VOLUME=SER=DEVHD2, 
//            DISP=(OLD,CATLG,DELETE),UNIT=SYSDA         
//DD2      DD DSN=MTHUSR.TEST.PDSFILE,VOLUME=SER=DEVHD2,   
//            DISP=(OLD,CATLG,DELETE),UNIT=SYSDA  
//*                                             
**************************** Bottom of Data ****************************

• SYSPRINT - Used by utility programs for their output.
• SYSOUT - Specifies system defined dd name used for file status codes, system abend codes information and output of the display statement.
• SYSDUMP - Used by the system for dumping when an abend occurs that causes a system dump.
• DD1 DD * - Specifies PS dataset with DISP for catalog (DISP=(OLD,CATLG,DELETE)).
• DD2 DD * - Specifies PDS dataset with DISP for catalog (DISP=(OLD,CATLG,DELETE)).