T - Technology (General)
TA - Engineering (General). Civil engineering
TC - Hydraulic engineering. Ocean engineering
TD - Environmental technology. Sanitary engineering
TE - Highway engineering. Roads and pavements
TF - Railroad engineering and operation
TG - Bridge engineering
TH - Building construction
TJ - Mechanical engineering and machinery
TK - Electrical engineering. Electronics. Nuclear engineering
TL - Motor vehicles. Aeronautics. Astronautics
TN - Mining engineering. Metallurgy
TP - Chemical technology
TR - Photography
TS - Manufactures
TT - Handicrafts. Arts and crafts
TX - Home economics
For more detailed information, visit the Library of Congress Classification Outline.
T - Technology (General)
TA - Engineering (General). Civil engineering
TC - Hydraulic engineering. Ocean engineering
TD - Environmental technology. Sanitary engineering
TE - Highway engineering. Roads and pavements
TF - Railroad engineering and operation
TG - Bridge engineering
TH - Building construction
TJ - Mechanical engineering and machinery
TK - Electrical engineering. Electronics. Nuclear engineering
TL - Motor vehicles. Aeronautics. Astronautics
TN - Mining engineering. Metallurgy
TP - Chemical technology
TR - Photography
TS - Manufactures
TT - Handicrafts. Arts and crafts
TX - Home economics