QA75 Electronic computers. Computer science QA76 Computer software 45 TK Electrical engineering. Electronics Nuclear engineering 25 HD28 Management. Industrial Management 19 QA Mathematics 17 L Education (General) 14 Q Science (General) 14 T58.5-58.64 Information technology 10 HF Commerce 8 H Social Sciences (General) 7 T Technology (General) 6 HE Transportation and Communications 5 LB2300 Higher Education 5 LB1603 Secondary Education. High schools 4 LC Special aspects of education 4 G Geography (General) 3 HD Industries. Land use. Labor 3 HG Finance 3 RC0254 Neoplasms. Tumors. Oncology (including Cancer) 3 TJ Mechanical engineering and machinery 3 TR Photography 3 TS Manufactures 3 ZA4050 Electronic information resources 3 GA Mathematical geography. Cartography 2 GC Oceanography 2 NA Architecture 2 RZ Other systems of medicine 2 T58.6-58.62 Management information systems 2 TA Engineering (General). Civil engineering (General) 2 Computer Science and Information System (Formerly known) 1