Examinations 2.242 Certification 1.476 Electronic data processing personnel 1.149 Study guides 874 Computer networks 649 Microsoft software 363 Telecommunications engineers 195 Maintenance and repair 192 English language 184 Computer technicians 136 Security measures 134 Internetworking (Telecommunication) 104 Microcomputers 100 Microsoft Windows (Computer file) 99 Computer security 98 Operating systems (Computers) 89 Examinations, questions, etc 85 Automobiles 84 Microsoft Windows server 69 Routers (Computer networks) 63 Test of English as a foreign language 59 Problems, exercises, etc 57 Database management 56 Automobile mechanics 55 Universities and colleges 52 Telecommunication 49 Study and teaching 48 Java (Computer program language) 47 International English Language Testing System 46 Study skills 44