The NTIS classification system has simpler notation than DDC. It does not recognize supporting table so that it can determine the notation faster. The number of the main class in NTIS classification system is 39 while DDC is 10. NTIS is most suitable for special libraries in the field of technology such as the Agency for the Assesment and Application of Technology (BPPT) since the system has a more specific technology subject. DDC is also effective for collection data exchange since 2010, referring that generally libraries in Indonesia has not recognized NTIS. Both systems actually have its advantages and disadvantages. In determining notations, both NTIS and DDC use the same initial step that is to determine the collection subject. NTIS is faster especially in handling technology subject. It is also more specific in referring technology subject. The number of the main class in NTIS is 39 while DDC is 10. Both systems have index. NTIS does not have supporting table while DDC has. NTIS uses a simpler notation because it uses only 2 digits. According to a key informant, the NTIS classification system does not recognize supporting table. In terms of notation search, NTIS's scheme is faster because it uses limited classification numbers. Index is mostly used for determining classification notation. Index in both systems is a clue represented in a systematically arranged letters. In NTIS, it can be figured out that subjects on technology is more specific yet in some certain categories is not as detail as DDC.