= 16 = 
  
APERTURE CARDS 
Advantages 
Can be easily indexed - 
30 lines film + 50 for computer index 
Easily updated 
Can be duplicated 
Can be used with automated storage 
and sorting equipment(80 line punch card) 
Used in Engineering Drawings, Maps, Survey Documents, 
Field Books etc. 
Jacket is normally 80 line computer card size and may 
contain both 35mm and l6mm copy. 
Disadvantages 
High cost 
Tendency to move away from punch card utilisation 
  
  
FILM FOLIOS 
Advantages 
Can accept a variety of films 
Easily added to or subtracted from 
Easily indexed 
Notes easily carried on face - and 
these can be duplicated 
Easily duplicated when the whole folio 
is transparent. : 
Used in a variety of "file" applications about a 
certain subject or person. It is virtually a "Hybrid" 
of the Aperture Card and Jacket systems. 
Size is normally 105mm x 148mm (4" x 6") 
Disadvantages 
High retrieval costs 
Machines not available for fast retrieval 
(hard copy) 
  
  
  
MICROFICHE 
Advantages and Disadvantages 
Dealt with as part of this report. 
  
  
  
Glendinning 4