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1.                 From The Free On-line Dictionary of Computing (19 January 2023):
                   
   
   
                   
                     
   Branch and Hang
   BRH
      <humour> (BRH) Originally a mythical instruction for the IBM
    1130 at Indiana University.
      Later some real examples were discovered.  The Texas
    Instruments TI-980 allowed all addressing modes with all
      instructions, including Store Immediate Extended (stores the
      value into the extension word of the instruction) and Branch
      and Link Immediate (makes a subroutine call to the same
      instruction -- Branch and Hang).
      Compare HCF.
      (1997-02-12)